WiMAX Planning Level III

WiMAX Planning

Level III

WiMAX Planning

Version Date Author Approved By Remarks

V1.0 2010/12/23 Not open to the Third Party

© 2010 ZTE Corporation. All rights reserved. ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used without the prior written permission of ZTE. Due to update and improvement of ZTE products and technologies, information in this document is subjected to change without notice.

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CONTENT

1 Chapter1 Overview and Process of Wireless Network Planning..................7 1.1 Definition of Wireless Network Planning .............................................................7 1.2 Objectives of WiMAX Network Planning .............................................................7 1.3 Process of WiMAX Wireless Network Planning ..................................................8

2 Chapter2 Network Dimensioning and Design ..............................................11 2.1 Requirements....................................................................................................13 2.2 WiMAX Cell Site Design....................................................................................14 2.3 WiMAX Network Deployment Scenario.............................................................16 2.4 Coverage Dimensioning....................................................................................18 2.5 Capacity Dimensioning .....................................................................................20 2.6 Joint Dimensioning............................................................................................23

3 Chapter3 Radio Propagation models ............................................................25 3.1 Main Propagation Mechanism Introduction.......................................................25 3.2 Standard Macro cell Propagation Model ...........................................................27 3.3 Cost231- Hata Model ........................................................................................29 3.4 Free-Space Model.............................................................................................31 3.5 SUI Model .........................................................................................................32

4 Chapter4 WiMAX Coverage Planning............................................................34 4.1 Overview of Link Budget ...................................................................................35 4.2 Physical Layer Basic Parameters in WiMAX.....................................................38 4.3 WiMAX Link Budget Table Introduction ............................................................42 4.3.1 Link Budget of the WiMAX System ...................................................................42 4.3.2 Structure of WiMAX Link Budget.......................................................................43 4.3.3 Input Parameters...............................................................................................44 4.3.4 Default Parameters ...........................................................................................45 4.4 Output Parameters............................................................................................52 4.4.1 Cell Radius Calculation .....................................................................................52 4.4.2 Site Number Estimation Based on Coverage Requirement ..............................52

5 Chapter5 WiMAX Capacity Planning .............................................................54 5.1 Principles of Subscriber Predication .................................................................54 5.2 Service Models..................................................................................................56 5.3 WiMAX Traffic Model ........................................................................................57 5.4 WiMAX Capacity Planning ................................................................................59 5.4.1 Physical Layer Traffic Calculation of Downlink .................................................59 5.4.2 Physical Layer Traffic Calculation of Uplink ......................................................60

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5.4.3 BS Throughput Calculation Principle ................................................................60

6 Chapter6 Site Survey and Planning ..............................................................63 6.1 Overview ...........................................................................................................63 6.2 Introduction to Site Survey ................................................................................64 6.3 Site Selection Principles....................................................................................65 6.3.1 No Obvious Blocking Objects around the Site ..................................................66 6.3.2 Site Height.........................................................................................................67 6.3.3 Avoid Interference with Other Systems.............................................................67 6.4 Ultra-Wide Coverage Site Survey and Selection ..............................................68

7 Chapter7 Antenna Selection ..........................................................................70 7.1 Overview ...........................................................................................................70 7.2 Antenna Selection .............................................................................................70 7.2.1 Frequency Range and Polarization Mode.........................................................71 7.2.2 Radiation Pattern, Horizontal BW, Vertical BW, and Gain ................................71 7.2.3 Downtilt Mode ...................................................................................................75 7.2.4 Side Lobe Suppression and Null Fill .................................................................77 7.2.5 Front-to-back Ratio, Maximum Input Power, Third-order Inter-modulation,

Isolation ............................................................................................................77 7.3 Selecting Antennas for Indoor Distribution Systems .........................................78

8 Chapter8 WiMAX Parameters Planning ........................................................80 8.1 Overview ...........................................................................................................80 8.2 Preamble & Neighbor Planning Flow ................................................................80 8.2.1 Frequency Planning Flow..................................................................................80 8.2.2 Preamble Planning Flow ...................................................................................81 8.2.3 Neighbor Planning Flow ....................................................................................82 8.2.4 Frequency Planning ..........................................................................................83 8.3 Preamble Planning Procedure ..........................................................................85 8.4 Neighbor Planning Procedure ...........................................................................86 8.5 ZXPOS CNO1 Planning Introduce ....................................................................88

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FIGURES Figure 1-1 Process of network planning ................................................................................8

Figure 1-2 Process of WiMAX wireless network planning ...................................................10

Figure 2-1 Process of WiMAX wireless network planning ...................................................12

Figure 2-2 Abstract of WiMAX deployment scenarios .........................................................17

Figure 2-3 SINR map for 1.3.1(FUSC) and 1.3.3(PUSC) schemes.....................................22

Figure 3-1 Propagation Mechanism.....................................................................................26

Figure 4-1 Fade margin – Probability distribution function...................................................37

Figure 4-2 Fade margin – Probability density function.........................................................37

Figure 5-1 Growth curve of cellular mobile telephony..........................................................55

Figure 6-1 Position of site survey in network planning.........................................................63

Figure 7-1 Antenna Selection in a Coverage Area with Great-fall Terrain...........................74

Figure 7-2 The Pattern Diagram of Radiation Range ..........................................................77

Figure 8-1 Network Planning Flow.......................................................................................80

Figure 8-2 Frequency Planning Flow ...................................................................................81

Figure 8-3 Preamble Planning Flow.....................................................................................82

Figure 8-4 Neighbor Planning Flow .....................................................................................83

Figure 8-5 FRS=4, 12, 3 ......................................................................................................84

Figure 8-6 FRS=1, 3, 3 ........................................................................................................85

Figure 8-7 Initial Neighbor List Planning ..............................................................................86

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TABLES

Table 2-1 Pathloss vs.WiMAXcell ......................................................................................16

Table 2-2 WiMAX Cell Count vs. Frequency .......................................................................16

Table 2-3 Cell Footprint for Different Ranges ......................................................................20

Table 3-1 Propagation Model default parameters................................................................29

Table 3-2 Constant Values for the SUI Model Parameters..................................................33

Table 5-1 Default configurations of the WiMAX traffic model ..............................................58

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1 Chapter1 Overview and Process of Wireless Network Planning

Knowledge

Definition of Wireless Network Planning ----------------------------Level 1 2

Characteristics of WiMAX Network----------------------------------- Level 1 2

Objectives of WiMAX Network ----------------------------------------Level 1 2

Process of Network Planning--------------------------------------------Level 1 2

1.1 Definition of Wireless Network Planning

Wireless network planning refers to the output of the network topology and main RF

parameters by using wireless network designing tools. The network planning should

meet the requirements of network construction and development and must be

implemented based on thorough field investigation and analysis. Besides, the

network planning should also consider the characteristics and main performance

indexes of the wireless equipment system.

1.2 Objectives of WiMAX Network Planning

The objectives of the WiMAX network planning are:

To maximize the time and area of wireless coverage.

To minimize the interference.

To improve the system capacity by using limited bandwidth.

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To meet the requirements of the data service in the prerequisite of

ensured voice service.

To plan the suitable wireless parameter configuration, and to enable the

system to provide the best service。

To reduce the number of equipment units and lower the cost of the

system in the prerequisite of ensured capacity and coverage

1.3 Process of WiMAX Wireless Network Planning

Figure1-1shows the processes of common network planning.

Figure 1-1 Process of network planning

Requirement analysis

Topology designing

Project planning

Site survey

Wireless network analysis

Plan outputVerification by

emulationPlan review

1. Requirement Analysis

This stage is the first step for network planning. According to communication

with customer RF planner should obtain the essential requirement and project

relative information. RF Planning engineer can refer to <RF Planning

Requirement Information Analysis List V1.0.xls>.

Requirement analysis report should contain relative necessary input

information、customer coverage and capacity requirement、KPI value need to

achieve、resource provided by customer etc.

2. Project Planning

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In accordance with customer requirement analysis, make out the project action

plan.

The plan should give out RF planning implementation task and timeline. The

large-scale and urgent task may be done in groups. In this case the

information of the groups should be provided and the resources and personnel

requirement must be confirmed by project implement unit.

3. Wireless Network Analysis

Wireless network analysis includes spectrum scanning and CW test. They are

both optional.

The purpose of spectrum is to learn the spectrum occupation situation in the

network planning area

There is no need to do spectrum scanning is such situations: there is no

interference according to the available information; If the customer does not

require spectrum scanning

The aim of CW test is to get the propagation model which can reflect

characteristics of planning area propagation environment, which is used to link

budge and simulation.

There is no need to do field test in these situations: the customer can provide

applicable radio propagation model; the radio propagation model in the model

database can reflect the characteristics of the radio propagation model in the

planning area; the network structure

4. Topology Design

On the basis of collected information, perform the coverage and capacity plan and design a network topology that theoretically meets the customer’s requirements, thus provide guidance for the subsequent work.

5. Site Survey

Find the sites that meet the requirements in the actual environment on the basis of the network topology design. To a larger network, it should judge whether the sites are qualified by network simulation

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6. Simulation

According to the customer’s requirement, use simulation software to output the simulation plot and effect verify the topology and perform the adjustment to the network planning.

7. Planning Out and Edit

When the planning work is completed, output the WiMAX network planning report or proposal; the report should be passed the internal checking and approving before being submitted to the customer; after the customer identifies the result, output the related reference and data. The project ends.

Figure1-2 shows the process of WiMAX wireless network planning when the input

and output are considered.

Figure 1-2 Process of WiMAX wireless network planning

Customerrequirements

Landform andtopography survey

BS performanceparameters

Requirementanalysis report

Available sitesurvey

Available sitesurvey report

Field strength measurementsite selection, field strengthmeasurement, and model

correction

Traffic distributionprediction

RF interferenceanalysis Link budget

Frequencysweep report

Model selection, site distribution planning, available siteselection, and planned site survey

Link budget

BS informationtable

Wireless parameter configuration(BS information table, model

selection, and antenna selection)

Electronic map Emulation

Emulationreport

Yes NoPlanning result

output Customer requirement satisfiedPlanning

report

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2 Chapter2 Network Dimensioning and Design

Knowledge

Requirements--------------------------------------- ---------------------Level 1 2

WiMAX Cell Site Design---------------------------------------------- Level 1 2

WiMAX Networks Dimensioning -------------------------------------Level 12

Designing, deploying, and managing any wireless cellular system requires clear

objectives to be identified from the outset. These includes definition of the footprint

coverage, the estimated number of users, the traffic load distribution, the

penetration and growth rate, and internet work access and roaming. Mobile WiMAX,

which will be deployed like 2G and 3G cellular networks, supports fractional

frequency. Fractional frequency reuse takes advantage of the fact that mobile

WiMAX user transmit on sub-channels and does not occupy an entire channel such

as in 3G. The objective of the radio network dimensioning and design activity is to

estimate the number of sites required to provide coverage and capacity for the

targeted service areas and subscriber forecast. This process is based on many

assumptions such as uniform distribution of subscribers, homogenous morphology,

and ideal site location. The main inputs required for network dimensioning are site

equipment-specific parameters, marketing-specific parameters, and licenses

regulation and propagation models.

Figure 2-1 shows the flow chart of activities performed in network design and

planning, starting from data collection of marketing and design requirement input

and achieving the business model to provide a nominal site plan using network

simulation software.

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Figure 2-1 Process of WiMAX wireless network planning

WiMAX access networks are often deployed in point-to-multipoint cellular fashion

where a single BS provides wireless coverage to a set of end users stations within

the coverage area. The technology behind WiMAX has been optimized to provide

both large coverage distances of up to 30 km under line-of-sight (LOS) situations

and typical cell range of up to 8 km under NLOS. In an NLOS, a signal reaches the

receiver through reflections, scattering, and diffractions. The signals arriving at the

receiver consists of many components from direct and indirect paths with different

delay spreads, attenuation, polarizations, and stability relative to the direct path.

WiMAX technology solves or mitigates the problem resulting from NLOS conditions

by using OFDMA, subchannelization, directional antennas, transceiver diversity,

adaptive modulation, error correction, and power control. The NLOS technology

also reduces installation expenses by making the under-the-eaves customer

premise equipment (CPE) installation a reality and easing the difficulty of locating

adequate CPE mounting locations.

Both LOS and NLOS coverage conditions are governed by propagation

characteristics of their environment, radio link budget, and path loss. In both the

cases, relays help to extend the range of the BS footprint coverage allowing for a

cost-efficient deployment and service.

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2.1 Requirements

Before network planning，requirements as bellow should be provided.

1. Service area(s): defined with geo coded polygons, including the size in

km2, and the terrain profile details (i.e., urban, suburban, rural, average

building height, etc.).

2. Coverage type: such as fixed-outdoor, on rooftop, or on outer walls,

fixed-indoor, nomadic outdoor/indoor, mobile outdoor or any combination

thereof.

3. Subscriber profile(s): such as residential, small business, corporate.

Subscriber profiles may relate to a specific type of coverage and service.

4. Subscriber distribution: subscriber numbers per profile, per service area,

and per deployment year, according to the scalability plan.

5. Service profile(s): such as VoIP, broadband Internet, VPN along with their

distinct characteristics (i.e., VoIP code, peak information rates, contention

factors, etc.). Service profiles may relate to specific subscriber profiles

and coverage types.

6. Available spectrum: defined as paired, along with local regulations

concerning the allowed channelization and duplex schemes.

7. Existing infrastructure: such as sites that can be reused, available

backhauling equipment with Ethernet interface, and core network PoPs.

8. Cartographic data: such as high-resolution digital maps with buildings.

9. Key performance indicators: such as coverage objective in terms of

percentage of the service area, differentiated per terminal type, where a

stable QPSK link can be achieved.

10. Customer requirement: such as duplex scheme, number of sectors/BS,

channel bandwidth, reuse scheme, type of sites, deployment strategy.

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During request for information (RFI)/RFP stages, a dimensioning exercise may be

requested by a customer, mainly for two reasons: either to acquire know how by

differentiated proposals or to identify the more cost-efficient solution. In the first

case, the requirements are usually relaxed so that the participant

vendors/integrators can design with flexibility, while the provided information (i.e.,

business plan, assets, and service areas) is hypothetical. The submitted studies will

probably be presented in various formats and most certainly based on diverse

assumptions. In such case a direct comparison among the studies is complicated,

and usually a more defined exercise is the next step. In the second approach, the

case study is well defined so that the design assumptions are either implied or

directly mentioned. The results are now directly comparable; hence a clear ranking

list can be obtained. From RF network designer point of view a different strategy

should be followed: showing flexibility in the network design and perhaps providing

several alternatives for the first approach, while a more strict, cost-optimum solution

is more appropriate for the second approach.

2.2 WiMAX Cell Site Design

One of the most important technical and business issues of any wireless technology

is efficiently (cost and performance) providing coverage and capacity, while

avoiding the build-out of a large number of new BSs. Cell design is performed with

the help of a network planning tool using digital elevation and demographic maps.

The first step in designing a wireless system is to develop a link budget.

Link budget is the loss and gain sum of signal strength as it travels through different

components in the path between a transmitter and receiver. The link budget

determines the maximum cell radius of each BS for a given level of reliability and is

comprised of two types of components: system related components and

non-system related components. These components are important factors when

evaluating the complexity and speed in deploying at higher frequency bands,

especially in unlicensed bands such as 5.8GHz (licensed in some countries such as

Russia). Other factors like interference from other surrounding networks will also

impact network performance and QoS.

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Path loss, shadow margin, environmental effects, and morphology are important

factors when planning for an optimum coverage. The morphology and physical

surroundings of a cell site play a very important role in determining the cell footprint.

A cell site footprint can shrink from 7 km in a mostly flat area with light tree densities

to 3 km in a hilly terrain with moderate-to-heavy tree densities. With adaptation of

Hata-cost 231 model, the cell size for several carrier frequencies from 2.3GHz to

3.5GHz is estimated for WiMAX systems using path loss propagation models for flat

rural, hilly rural, and urban environment.

Table 2-1 illustrates a comparison of a path loss simulation for a WiMAX system for

different frequency bands. In this study, a link budget of 142dB which provides 3km

cell coverage at 1900MHz has been assumed. To obtain the same cell radius of

3km with 2.5GHz frequency band an additional 4dB for link budget is needed. In a

coverage limited design scenario, this 4dB corresponds to 22 percent reduction in

cell coverage footprint and almost 70 percent increase in the cell count. Table 2-2

shows cell count calculation for 1900MHz to 3.5GHz to illustrate the impact that

path loss can have, especially when deploying in higher frequency bands.

WiMAX systems implement advanced radio features that compensate for the extra

attenuation resulting from higher carrier frequency, larger transmission bandwidth,

and higher indoor penetration. The radio enhancement feature applicable to the

fixed and mobile WiMAX is sub-channelization.

Other enhancement features that are only applicable to mobile WiMAX are

convolution turbo coding, repetition, and HARQ.

Applying smart antennas or MIMO configuration in different topologies will enhance

the cell site coverage footprint. Cell planning options and WiMAX technology

features also allow interference and noise handling so that WiMAX can provide

sufficient coverage.

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Table 2-1 Pathloss vs.WiMAXcell

Table 2-2 WiMAX Cell Count vs. Frequency

2.3 WiMAX Network Deployment Scenario

A major feature of WiMAX compared to other wireless access technologies is that it

breaks the barrier of addressing a single customer profile. Global system for mobile

communications (GSM)/universal mobile telecommunications system (UMTS)

provide mainly voice and low speed internet to mobile subscribers, while local

multipoint distribution service (LMDS)/wireless local loop (WLL) offer higher

bandwidth services to fixed subscribers. WiMAX can offer broadband services to all

fixed, nomadic, and eventually mobile subscribers, according to the aims of the

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latest IEEE 802.16e standard. This major advantage for WiMAX technology offers

greater flexibility and scalability; however it presents more design challenges. A

conceptual presentation of deployment scenarios, based on equipment, services,

and potential customer profiles is presented in Figure 2-2.

Figure 2-2 Abstract of WiMAX deployment scenarios

Each “sector” represents a WiMAX terminal profile:

• Fixed-outdoor units (including antenna, RF subsystem, modem), which can

be installed on the rooftop or outer building walls for maximizing link

performance. A cable connects the unit to an indoor interface terminal that

provides Ethernet and VoIP ports.

• Fixed/portable indoor units (intergraded antenna, RF base band and

interface in a single box), which are installed indoors close to a window or the

outer wall. The unit is portable within the indoor space, however it requires

power supply.

• Nomadic/mobile units (PCMCIA cards, handheld devices), which are truly

portable (mobile in future versions) and can be used in outdoor and indoor

spaces.

Each terminal profile is built with different performance capabilities and cost

towards specific customer profiles. Fixed-outdoor terminals are capable of long

range, robust links that can transfer high-bandwidth and delay sensitive services

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with low impact on network air-interface resources; hence they are more suitable for

corporate, small-to-medium enterprises (SMEs), and small-offices-home-offices

(SOHOs). The higher hardware and installation costs are balanced by higher

revenues.

Fixed-indoor terminals have considerably less cost and are self-installable, albeit

with smaller link range. Such terminals address the mass market of residential

access. Finally the nomadic and portable terminals require even greater network

design margins and usually address individual customers at specific service areas

(such as community/camp networks).

As WiMAX technology progresses, more system gain will be achieved in the

air-interface thus resulting in higher cell ranges and increased percentage of

nomadic terminals mainly at the expense of fixed-indoor units.

The continuous development of WiMAX technology from IEEE 802.16-2004

standard to the IEEE 802.16e amendment, has led to significant improvements in

the air-interface. Recent advances include higher BS transmit power, advanced

antenna systems (MIMO, beamforming (BF)), improved radio resource

management through the OFDMA profile, improved coding techniques which

reduce the signal-to-interference and noise ratio (SINR) thresholds, efficient uplink

(UL) subchannelization, and flexible frequency reuse. The current amendment of

WiMAX offers more than 15 dB increase in the system gain over previous versions

which drastically extends the radio coverage, and can therefore reach indoor

customers even when using portable/mobile terminals.

As the WiMAX system gain increases due to the continuous enhancement of the

air-interface, in the context of dimensioning, the network size for a specific

deployment is reduced, and so is the up-front investment.

2.4 Coverage Dimensioning

A primary objective when designing a WiMAX network is to provide radio coverage

to a specified service area and type of subscribers. The purpose of coverage

dimensioning is to ensure that a sufficient number of BS will be deployed and that

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the resulting coverage will satisfy the performance indicators. The process is simple:

the service area (km2) is divided by the cell footprint to produce the necessary

points of presence (PoP) where a WiMAX BS will be deployed. The service area is

defined in the business plan; however the cell footprint depends on the deployment

scenario and product configuration/performance. To calculate the cell footprint, a

very significant step is to estimate the maximum system range.

The maximum system range is defined as the range for which the system can

achieve a performance threshold, usually in terms of received signal strength (RSS).

RSS is estimated by Equation 2.4 and takes into consideration the system gains

such as transmitter power P, the antenna gains (per element, BF, MIMO) G, the

signal processing gains (HARQ, repetition) Gsp, the system losses such as

distance-dependent path loss with shadowing and fading Ld, the penetration loss

Lp, and the design margins (implementation, coverage reliability, mobility,

interference) M.

S = P + G + Gsp − Ld − Lp − M (dB)-----------------------------------------2.4

The RSS (S) threshold depends on the signal-to-noise ratio (SNR) threshold and

the noise floor (Nth). For proper system operation there is an SNR value for which

the decoding of the received signal results in lower than 10-6 bit error rate (BER).

Since the SNR thresholds depend on the modulation and coding scheme (PHY

mode), the maximum system range that corresponds to the RSS of the lower

scheme is considered i.e. QPSK. For Mobile WiMAX and considering a 5MHz

channel bandwidth a typical value would be around S = −97dBm.

As mentioned above, the maximum system range depends on the deployment

scenario and product configuration. For example MIMO technology can add the

antenna gains. In general for different terminals (fixed outdoor, indoor) the TX

power, gains, losses, and noise Figure can differ substantially. Another parameter,

which is terminal independent, is the area coverage reliability. Such an indicator

can be defined as “achieving a available traffic link at xx% of locations in a cell and

for xx times availability,” hence affecting the shadow margin and fast fading

components of the path loss.

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The BS footprint is estimated by the operating system range which, depending on

the deployment scenario, can be the maximum or a percentage of it. For rural areas

and outdoor terminals the maximum range can be used, however, for urban areas

and mobile terminals a certain overlap among adjacent cells may be desirable for

mobility and handover. For mobile WiMAX networks, the hexagonal cell structure is

preferred. Usually the single site coverage area can be calculated by Equation 2.5

where r is the radius. (3cells)

Fhex = 9* 3 r2 /8-----------------------------------------------------------------------2.5

The result of Equation 2.5 provides nonadjacent cell overlapping footprint. To

assume that the whole footprint is available, at least three sectors per cell are

necessary. The relation between the operating range, the footprint, as well as an

indication of the required PoP to cover a particular area of 100 km2 is highlighted in

Table 2-3.

Table 2-3 Cell Footprint for Different Ranges

2.5 Capacity Dimensioning

Further to providing adequate radio coverage to customers, the next same

important objective is to ensure sufficient air-interface capacity (throughput) to offer

a wide range of services. Given a business plan, the network capacity is decided by

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the potential subscriber number and the required rates for various services, as

discussed in capacity planning. The purpose of capacity dimensioning is to convert

the needed capacity into number of sectors, which then have to be distributed for

the estimated number of PoP. Another parameter is sector average throughput,

which finally determines how many subscribers can be served in a sector. For

pre-sale network planning project, define the average sector throughput in theory

mainly has relation with some parameters such as:

Available spectrum

Symbol allocation for downlink and uplink

Frequency Reuse patter

Site configuration: MIMO selection mechanism、Beamforming or FFR

The sector throughput is usually provided as recommendation for the system

vendor, however it vary a lot depending on the deployment scenario. Within one site

coverage area, different location users will obtain various throughputs. The upper

throughput bound can be achieved for a non-interference sector where terminals

are located only in the 64QAM5/6 region, achieving around 17 Mbps for 5MHz

bandwidth and use Matrix B. During practical deployments, the terminals will be

scattered across the whole cell footprint, hence operating in various modes.

Furthermore, interference due to frequency reuse may further downgrade the PHY

mode for a particular terminal, especially if the number of channels is limited. A

default assumption is to consider, as average sector throughput, the one

corresponding to 16QAM1/2. Thereafter if the deployment conditions are favorable,

as in the case of fixed-outdoor terminals or when enough spectrums is available for

relaxed reuse, higher throughput should be expected. The throughput can be also

enhanced by means of MIMO techniques and this should also be taken into account.

It should be noted that the full usage of subchannels (FUSC) permutation scheme,

where all subchannels are allocated to users, hence the whole channel is exploited.

In case segmentation is considered, i.e., partial usage of subchannels (PUSC), the

users in a sector utilize a specific segment (1–6 subchannels), and therefore the

throughput in this case is reduced accordingly. Sub channel allocation in the DL

may be performed in the following ways: partial usage of subchannels (PUSC)

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where some of the subchannels are allocated to the transmitter and full usage of

the subchannles (FUSC) where all subchannel are allocated to the transmitter.

Based on the standard, there will be regions in the DL and UL subframes for both

FUSC and PUSC and in this case an average throughput condition should be

expected. In most products, during the sector configuration, an RF designer can

select or exclude segmentation according to deployment conditions. The process of

selecting frequency reuse and channel allocation in sectors is very important for

both capacity and coverage. In mobile WiMAX this can be done in a flexible manner,

although frequency planning cannot be avoided. This is due to the possibility of non

uniform network layout, in most cases, where reasonable frequency planning may

improve performance. According to mobile WiMAX terminology the reuse is

denoted as 1.x.y, where x denotes the cell sectors and y the available channels.

There are two main schemes under consideration: global reuse 1.x.1, where a

single channel is used everywhere and cell/cluster reuse 1.x.y, where y = nx, n = 1,

2, 3. The most appropriate scheme is adopted, based on the systems’ special

capabilities to reject or tolerate interference (i.e., via BF). An indicative performance

of the most common schemes for nomadic/mobile terminals (most sensitive to

interference) is presented in Figure 2-3.

Figure 2-3 SINR map for 1.3.1(FUSC) and 1.3.3(PUSC) schemes

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It can be observed that for the 1.3.1 scheme the SINR drops well below the 3 dB

threshold for the lowest modulation scheme, QPSK, hence a significant part of the

cell footprint, especially among adjacent sectors, has no coverage. In the case of

the 1.3.3 scheme, the interference appears closer to the cell edges and hence the

coverage blanks spots are much smaller. It should be noted that in the 1.3.3

scheme the higher order PHY mode schemes extend to a larger region, hence

indicating an improved sector throughput. Furthermore, when employing PUSC

instead of FUSC, the 1.3.1 scheme behaves essentially as 1.3.3, while 1.3.3 as

1.3.9. It is typical for a sector to operate in 1.3.1 FUSC mode for terminals with good

link quality and short link distance and in PUSC mode, which is equivalent to 1.3.3

for terminals that would otherwise achieve low SINR(due to low signal strength or

interference).

Knowing the average sector throughput as described in previous paragraphs,

capacity dimensioning can be completed as follows: Initially an analysis on the

customers that can be accommodated in a sector is performed. This is done by

analyzing the service plan and calculating the average data and VoIP CIR per

service and customer.

2.6 Joint Dimensioning

In Chapters 2.6 and 2.7, the number of PoP and sectors were estimated according

to the requirements of a dimensioning project. The final step, as shown in Figure

2-1, is to combine these results into the optimum BS configuration. Clearly the

estimated PoP and sectors are the absolute minimum according the needs of

coverage and capacity, respectively. At this stage joint consideration may suggest

that more PoP or sectors may be necessary. There are three possible conditions:

Balanced network: The number of PoP approaches 1/x of the number of

sectors, which means that in each PoP roughly x sectors will be deployed.

The number of sectors for blanket coverage should be 3 < x < 6, where x

= 3 for Mobile WiMAX. This condition ensures both the integrity of the

footprint and satisfies the capacity requirement.

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Coverage-limited network: The network is coverage limited and in this

case the number of sectors should be increased until the previous

condition is met. The fact that the original business plan leads to a

coverage limited network should be stated in the dimensioning study.

CapEX is driven by coverage performance indicators, while the additional

sectors will further increase the air-interface capacity. Operators may

want to revise the size of the service area, or exploit the additional

capacity.

Capacity-limited network: The number of PoP is quite lower than 1/3 of

sectors, which indicates either additional PoP or higher sectorization

(sectors/PoP). Increasing the number of PoP will trigger additional CapEX

and OpEX in terms of site acquisition and preparation. Therefore, if a

higher sectorization scheme is possible, such as when the terminals are

fixed outdoor, fixed-indoor, or nomadic where handover is not necessary,

it should be preferred as a cost-optimum solution. When the network

needs to accommodate mobile terminals and provide handover capability,

the sectors should be 3 < x < 4 and more PoP may be needed. An

alternative approach would be to deploy a dual layer cell where 6 sectors

of 120◦ are used; however each pair of sectors (i.e., 1 and 4) is assigned

the same azimuth. For a dual layer cell at least 6 channels are necessary

for the frequency reuse of 1.3.3.

The selected number of sectors per PoP defines the BS configuration in terms of

frequency reuse/channel assignment, and antenna beamwidth/azimuth/tilt, while

other air-interface parameters are not related to dimensioning. Capacity or

coverage dimensioning should be revised based on the above-mentioned

conditions, for coverage or capacity limited cases, respectively. A comparison

between initial requirement and actual achievement should be included in the

dimensioning study.

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WiMAX Planning

3 Chapter3 Radio Propagation models

Knowledge

Free-space Model------------------- --------------------------------------Level1 2

SUI Model--------------------------- --------------------------------------Level3 4

Macro cell Model----------------------------------------------------------Level3 4

In any wireless network planning project, the radio model is a key component; it has

close relation with cell radius estimation and simulation. Because of the variety of

the propagation environment, there is no universal propagation model for different

scenario and different frequency band. In general, radio models can be almost

arbitrarily complex. However, working with such models can be very

computationally intensive and it is important to find the model with the right balance

of abstraction and complexity for the problem under study. For the WiMAX network

planning problems, two propagation models can be suitable and are described

below.

3.1 Main Propagation Mechanism Introduction

The main propagation mechanisms defined by the ray theory are explained in this

Chapter. As small wave lengths, i.e., higher frequencies are considered, the wave

propagation becomes similar to the propagation of light rays. A radio ray is

assumed to propagate along a straight line bent only by refraction, reflection,

diffraction or scattering. The following content will give some simple introduction for

the several kinds propagation mechanisms.

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WiMAX Planning

Figure 3-1 Propagation Mechanism

Reflection

The reflection phenomenon is the mechanism by which a ray is reflected at an

angle equal to incidence angle. The reflected wave fields are related to the

incident wave fields through a reflection coefficient which is a matrix when the

full polarimetric description of the wave field is taken into account. Usually we

will consider constant reflection coefficients to simply the computations.

Diffraction

The diffraction process in ray theory is the propagation phenomena which

explain the transition from the light region to the shadow regions behind the

corner of a building or over the roof-tops. For the case of multiple diffractions,

the complexity increases dramatically.

Scatter

Rough surfaces and finite surfaces scatter the incident energy in all directions

with a radiation diagram which depends on the roughness and size of the

surface or volume. The dispersion of energy through scattering means a

decrease of the energy reflected in the specula direction. This description

does not take into account the true dispersion of radio energy in various

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WiMAX Planning

directions, but account for the reduction of energy in the specula direction due

to the diffuse components scattered in all directions.

Penetration and Absorption

Penetration loss due to building walls have been investigated and found very

dependent on the particular situation. Absorption due to trees or the body

absorption are also propagation mechanisms difficult to quantify with

precision.

Another absorption mechanism is the one due to atmospheric effects. These

effects are usually neglected in propagation models for mobile communication

applications at radio frequencies but are important when higher frequency (e.g.

60GHz) is used as described.

Guided wave

Wave guiding can be viewed as a particular propagation mechanism to

describe the propagation in street canyon, in corridors or tunnels. The wave

guiding phenomena can be explained on multiple reflections or propagation

modes.

3.2 Standard Macro cell Propagation Model

Now in WiMAX link budget and simulation, we usually adopt standard macrocell

model. This model is a mapping from the Hata-COS231 formula. It is used for

macro cellular path loss prediction according to the formula shown below.

With the parameters as:

K1, K2: Intercept and slope. These factors correspond to a constant offset (in

dB) and a multiplying factor for log of distance between transmitter and

receiver.

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WiMAX Planning

K3: Receiver antenna height factor. Correction factor is used to account for the

effective receiver antenna height.

K4: Multiplying factor for Hms.

K5: Effective transmitter antenna gain. This is the multiplying factor for the log

of the effective gain.

K6: Multiplying factor for log(Heff)log(d).

K7: Multiplying factor for diffraction loss calculation.

d: Distance between the receiver and the transmitter (m)

Hms: Effective height of the receiver antenna (m)

Heff: Effective height of the transmitter antenna (m)

Diffn: Diffraction calculation using either the Epeterson, Bulinfton, Deygout or

Japanese Atlas knife edge techniques

C_Loss: Clutter specifications taken into account in the calculation process.

As to different frequency band, this table lists some default parameters.

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WiMAX Planning

Table 3-1 Propagation Model default parameters

These propagation models are used in the conditions bellow:

Site in environments where the distance from the site is greater than

approximately 500m

Base station antenna height in the range of 15-200m

Receiver heights in the range of 1-10m

3.3 Cost231- Hata Model

Path loss estimation is performed by empirical models if land cover is known only

roughly, and the parameters required for semi-deterministic models cannot be

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WiMAX Planning

determined. Four parameters are used for estimation of the propagation loss by

Hata’s well-known model include: frequency f, distance d, base station antenna

height hBase and the height of mobile antenna hMobile. The Hata’s model is based on

Okumara’s various correction functions, for urban area the basic transmission loss

Lb calculation for Okumara model as following:

A(h Mobile) equation is following:

This model is suitable to:

f : 150----1000MHz

hBase : 30----200MHz

hMobile : 1----10m

d : 1-----20km

Cost231 has extended Hata ’s model to the upper frequency band 1500-2000 MHz.

This combination is called “Cost-Hata-Model”:

Where a(h Mobile) is defined same as the above equation.

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WiMAX Planning

The Cost-Hata-Model is suitable to the following scenario

f : 1500----2000MHz

hBase : 30----200MHz

hMobile : 1----10m

3.4 Free-Space Model

What is free space? Actually it means space with nothing at all in it. The important

features: uniform everywhere, contain no charge, and carries no current, infinite

extent in all dimensions, like this does not exist but interstellar space is a good

approximation.

The free-space model (originally published by H.T. Friis in 1946) is the simplest

model that can only be applied in open area, i.e., no obstruction on the transmission

line. This model is considered as a standard propagation model, a reference and

benchmark of all other propagation models.

The path loss of the free-space model is

Lfs( f , d) = 32.44 + 20 log10 f + 20 log10 d ------------------------------------------(3.1)

Where

Lfs is the free space path loss in decibels

d is the distance between the transmitter and the receiver in kilometer

f is the frequency in MHz

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WiMAX Planning

In the free space model, many factors, such as reflection/multipath, shadowing,

fading, atmosphere factors, etc., that may affect radio on its transmission path are

omitted. This model, consequently, does not capture key transmission

characteristics of radio, so it is not a very appropriate model for real world

scenarios.

3.5 SUI Model

The Stanford University Interim (SUI) model was developed for design,

development, and testing in the multipoint microwave distribution system frequency

band [9] (2–3GHz). It was recommended by the IEEE 802.16 standard body. The

SUI model is valid for radio propagation within the 2–3 GHz range and has different

parameter settings for urban, suburban, and rural scenarios. The maximum path

loss (type A) is hilly terrain with moderated-to-heavy tree density. The minimum

path loss (type C) is mostly flat terrain with light tree densities. The intermediate

path loss condition is type B.

The SUI model is used for receiver’s antenna height between 2 and 10 m. The path

loss model is given by

LSUI(d, f , hm) = A + 10δlog10 (d/d0)+ Xf + Xh + s, for d > d0-------------- 3.2

with the correction factors for the operating frequency and for the

customer-premises equipment (CPE) antenna height of the model:

Xf = 6 log10 (f/2000) ----------------------------------------------------------------3.3

Xh = −10.8 log10(hm/2), for terrain type A and B --------------------------------3.4

Xh = −20 log10(hm/2), for terrain type C -----------------------------------------3.5

Where

LSUI is the SUI path loss in decibels

d is the distance between the BS and the CPE antennas in meters, d0 = 100 m

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WiMAX Planning

hm is the CPE height above ground

s is a log normally distributed factor that is used to account for the shadow

fading owing to trees and other clutter and has a value between 8.2 and 10.6

dB.

The other parameters are defined as

A = 20 log10(4πd0/λ)-----------------------------------------------------------------3.6

δ = a − bhb − c/hb ---------------------------------------------------------------3.7

where

hb is the base station height above the ground in meters and should be

between 10 and 80m parameters.

a, b, c are the constants dependent on the terrain type and are shown in Table

3-2.

The SUI model was chosen to be used in the following network planning models

based on the following reasons: (1) the model was accepted by the IEEE 802.16

standard body; (2) it has a good compromise between simplicity and accuracy, i.e.,

it models the key characteristics of the radio frequency and it is simple,

computationally with a relatively small number of parameters.

Table 3-2 Constant Values for the SUI Model Parameters

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WiMAX Planning

4 Chapter4 WiMAX Coverage Planning

Knowledge

Overview-------------------------------------------- ---------------------Level12

Parameters---------------------------------------------------------------- Level 12

Input and output----------------------------------------------------------Level 12

LB--------------------------------------------------------------------------Level 12

In WiMAX planning, the coverage planning is performed based on link budget.

The coverage of each base station (BS) in a WiMAX network is affected by the

following factors:

Antenna height

Antenna gain

Horizontal field angle

Vertical field angle

Azimuth

Downtilt angle

Transmit power

To predicate the coverage exactly, the propagation model used in coverage

predication must take the preceding factors into consideration.

ZTE choose tuned cost-231 model for WiMAX coverage predictions. In link budget

table and simulation software, the propagation model parameters in general model

form will be used

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WiMAX Planning

4.1 Overview of Link Budget

In the cellular system, a BS sector covers such an area where the receiver (BS or

terminal) shall have efficient signal levels to satisfy service requirements.

In a certain propagation environment, the coverage of a cell directly depends on the

maximum allowable path losses between transmitting and receiving ends, while link

budget can determine the maximum allowable path loss of the specified radio link.

In the link budget, the maximum allowable path loss can be calculated with

following formula:

Maximum allowable path loss = Transmit power – Receiver sensitivity – Margin

+Gain

The Path loss is related to four parts:

Transmit power

Receiver sensitivity

System margin

System gain

The transmit power refers to the effective transmit power of the antenna and it can

be either the equivalent isotropic radiation power (EIRP) or equivalent radiation

power(ERP)

EIRP=transmit power (dBm)+transmit antenna gain(dBi)-Feeder and jumper

loss(dB)-other loss(dB)

The receiver sensitivity refers to the minimum signal level required at the receiving

end of the antenna with a specified data rata and channel condition.

The margin includes the fading margin, penetration loss, and interference margin.

Fading margin

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WiMAX Planning

The fading margin is reserved to overcome fade changes and ensure the

reliable communication in the cell. It is related to the communication probability

at the cell edge.

In the wireless propagation through space, the path loss changes rapidly in

any specified distance. The path loss can be seen as a random variable that

follows the lognormal distribution. If the network is designed based on the

average path loss, the chances that the loss at the cell edge is greater and

less than the path loss medium are the same, that is, 50%. In another word,

the cell edge coverage ratio is only 50%. Hence, the probability of subscribers

at the cell edge failing to get the expected QoS is 50%. To improve the cell

coverage, the fade margin must be reserved. Take the edge coverage ratio of

70% as an example:

Suppose the random variable of propagation loss isζ . Then ζ follows the

Gauss distribution of dB. The average of the variable is m, the standard

deviation is δ , and the corresponding probability distribution function is δ .

Assume the loss threshold to 1ζ . When the propagation loss exceeds the

threshold, the signal strength cannot meet the requirements of the expected

QoS on demodulation. Hence, the probability of the edge coverage ratio 75%

can be calculated as follows:

∫∞−

−−

=<=1

2

2

2)(

1cov 21)(

ζδ

ζ

ζδπ

ζζ dePPm

rerage

In the case of an outdoor environment, the standard deviation of the random

variable propagation loss is usually assumed to 8 dB. Therefore, the margin

for the edge coverage probability 75% is:

dBm 4.58675.0675.01 =×==− δζ

错误！未找到引用源。 and 错误！未找到引用源。 show the probability distribution

function and probability density function respectively.

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WiMAX Planning

Figure 4-1 Fade margin – Probability distribution function

Mean m

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%

0%

0.675 x Standard deviation

Probability distribution function

Independent variable

Figure 4-2 Fade margin – Probability density function

Propagation loss

Normal distribution-compliedprobability density function

m

Standard deviation = 8 dB

0.675 x 8=5.4dB

Threshold

The Figures show that, in network planning and designing, a margin of at least 5.4

dB must be reserved for an edge coverage ratio of 75%. If an edge coverage ratio

of 90% is required, a 10.3 dB margin must be reserved.

1. Penetration loss

Penetration loss usually adopts the experience value, depending on the

factors such as construction materials and thickness of building wall in

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WiMAX Planning

different places. The descending order of the penetration loss is normally as:

dense urban area, urban area, suburban and rural area. For the link budget,

generally the penetration loss of the dense urban is 18dB, urban area 15dB,

suburban 12dB and rural area 8dB. In the actual planning, more accurate

penetration loss can be obtained through test.

2. Interference Margin

This parameter value is a reserved margin for frequency reuse brings

co-channel interference effect. Interference margin have a relation with

frequency reuse pattern and clutter type. Now link budget use 2dB for

downlink and 3dB for uplink, this default value come from forum white paper. If

frequency channel numbers more than 6, this value will consider change to

less one.

4.2 Physical Layer Basic Parameters in WiMAX

The following table lists the basic physical layer parameters of partial usage of

subchannels (PUSC) in the 10MHz WiMAX system.

Para. Unit Value

BW MHz 10

Nused N/A 841

n N/A 28/25

G N/A 1/8

Nfft N/A 1024

Fs kHz 11200

Δf kHz 10.93750000

Tb us 91.4286

Tg us 11.4286

Ts us 102.8571

Sampling Time us 0.0893

Frame Duration ms 5

Symbol Num. N/A 48.61

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WiMAX Planning

Repeat Time N/A 1.00

Implement Loss dB 3.00

NF dB 4.00

SNR dB 5

RSS dBm/840subcarriers -92.37

Descriptions of the parameters:

1. BW: System bandwidth

2. Nused: Number of used sub-carriers. In the 10 MHz system, the number of

used sub-carriers is 841, including data sub-carriers, pilot sub-carriers, and

one DC sub-carrier.

3. n: Sampling factor. In the 10MHz system, its value is set to 28/25.

4. G: Cyclic prefix (CP) factor. It is the ratio of the CP duration in an OFDM

symbol (time domain) to the used symbol domain. The value is often set to 1/8.

5. Nfft: Number of FFT size. In the 10 MHz system, the value is set to 1024.

Its strict physical definition is the minimum value that exceeds Nused. It is the

Nth power of 2.

6. Fs: Sampling frequency. It is calculated according to the formula: Fs =

floor(655r45r433323n×BW⁄ 8000)× 8000;

7. Δf: Sub-carrier bandwidth. It is calculated according to the formula: Δf =

Fs/ NFFT;

8. Tb: Used symbol duration. It is calculated according to the formula: Tb = 1

⁄ Δf;

9. Tg: Cyclic prefix duration. It is calculated according to the formula: Tg = G

*Tb.

10. Ts: OFDM symbol duration. It is calculated according to the formula: Ts =

Tb + Tg;

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WiMAX Planning

11. Sampling Time: It equals Tb/NFFT;

12. Frame duration: 5 ms;

13. Symbol Num.: Number of OFDM symbols. It is calculated according to the

formula: Symbol Num.= Frame Duration*1000/Ts;

14. Repeat Time: Number of repetition times (different from the definition of

retransmission);

15. Implement Loss: Implementation loss. It is the difference between the

baseband link simulation result and the actual system performance. It is often

assumed to 3 dB, though the recommended value of related standards is 5 dB;

16. NF: Noise Figure. In this document, the NF of the system side is set to 4

dB;

17. SNR: Signal-to-noise ratio. The value is set to 5dB, corresponding to

QPSK 1/2;

18. RSS: Receiver sensitivity. In this document, the RSS refers to the RSS of

the system side and is calculated according to the following formula:

Because the basic physical layer parameters of PUSC in the 10MHz system are

described in detail, the parameters of the 5MHz and 7MHz systems are not detailed

in this document. The following table lists the corresponding values of the two

systems.

Values of basic physical layer parameters of PUSC in the 5MHz system

Para. Unit Value

BW MHz 5

Nused N/A 421

n N/A 28/25

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WiMAX Planning

G N/A 1/8

Nfft N/A 512

Fs kHz 5600

Δf kHz 10.93750000

Tb us 91.4286

Tg us 11.4286

Ts us 102.8571


Frame Duration

ms 5



Implement Loss

dB 3.00

NF dB 4.00

SNR dB 5

RSS dBm/421subcarrie

rs -95.37

From the RSS results, it can be seen that the sensitivity of the 5 MHz system is 3

dB higher than the 10 MHz system. This is because that the bandwidth of the

5 MHz system is only half of the 10 MHz system.

The following table lists the basic physical layer parameters of the 7 MHz system.

Para. Unit Value

BW MHz 7

Nused N/A 841

n N/A 8/7

G N/A 1/8

Nfft N/A 1024

Fs kHz 8000

Δf kHz 7.81250000

Tb us 128.0000

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WiMAX Planning

Tg us 16.0000

Ts us 144.0000


Frame Duration

ms 5



Implement Loss

dB 3.00

NF dB 4.00

SNR dB 5

RSS dBm/840subcarrie

rs -93.83

4.3 WiMAX Link Budget Table Introduction

The following introduction base on the version<WiMAX LB V2.0 20100610>

4.3.1 Link Budget of the WiMAX System

The link budget of the WiMAX system involves three application scenarios: fixed 、

nomadic and mobility. In the case of a wireless communication network, the link

budget for the three scenarios should consider both the indoor coverage

requirement and outdoor coverage requirements

Combine the indoor coverage and nomadic scenario, it is indoor coverage mode,

terminal is PCMCIA card、USB dongle or indoor CPE

Combine the outdoor coverage and fix scenario; it is outdoor CPE application

mode.

Combine the outdoor coverage and mobility scenario; it is outdoor USB application

mode.

At present, five channel models are used in the link simulation:

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WiMAX Planning

AWGN

PB 3 km/h

VA 30km/h

VA 60km/h

VA 120km/h

Now mostly WiMAX network is nomadic application, so channel mode select PB

3km/h.

4.3.2 Structure of WiMAX Link Budget

The link budget of the WiMAX system includes 11 parts:

1. RF Planning Input&Output: list all input parameters and output site

number

2. Dense Urban: Link budget table of dense urban areas

3. Mean Urban: Link budget table of common urban areas

4. Suburban: Link budget table of suburban areas

5. Rural: Link budget table of rural areas

6. ShadowMarginCal.: Calculation of shadow fading margin value

7. 5MHzSys.: Parameter calculation of the 5 MHz WiMAX system

8. 7MHzSys.: Parameter calculation of the 7MHz WiMAX system

9. 10MHzSys.: Parameter calculation of the 10 MHz WiMAX system

10. SNR: list SINR values involved in the link budget table

11. Traffic Model: Traffic model of the WiMAX system

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WiMAX Planning

4.3.3 Input Parameters

Two types of input parameters are involved, including the parameters that must be

provided by the customer or the user and the default parameters recommended by

the WiMAX project team.

4.3.3.1 Compulsory Input Parameters

This type of parameters must be entered by the user. The following table lists the

parameters:

Item

Service Area Name

Frequency Band

Channel Bandwidth

Number of Channel

DU Area

U Area

SU Area

R Area

Number of Subscriber

Coverage Level

Application Scenario

Descriptions:

1. Service Area Name: Name or the boundary of the service area

2. Frequency Band: Frequency band of the system. It may select from 2300

MHz 、2500MHz or 3500MHz.

3. Channel Bandwidth: Bandwidth of the system. It must be 5 MHz 、7MHz or

10 MHz. Channel bandwidth will have a effect to symbol and subchannel

number.

4. Number of Channel: Number of available channels or carriers of the

system. The value must be 1, 3, 6, 9, or 12.

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WiMAX Planning

5. DU Area: Size of dense urban areas in the service area, unit in km2;

6. U Area: Size of common urban areas in the service area, unit in km2;

7. SU Area: Size of suburban areas in the service area, unit in km2;

8. Rural Area: Size of rural areas in the service area, unit in km2;

9. Number of Subscriber: Number of subscribers in the service area. The

traffic requirement is calculated according to the default traffic model. See

chapter 8 for the introduction to the default traffic model.

10. Coverage Level: Coverage level requirement. The level must be indoor

coverage or outdoor coverage.

11. Application Scenario: The application scenario must be mobility or fixed

access.

4.3.4 Default Parameters

These parameters must be entered in the link budget of the WiMAX system.

Because these parameters involve too many aspects, only the default parameters

are specified in this document.

4.3.4.1 RF Scenario Setting

1. RF Reuse: The parameter is selected according to the number of channels.

When the number of channels is 1, the parameter should be set to 1*1*3;




When the number of channels is 12, the parameter should be set to

4*12*3.

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WiMAX Planning

2. Interference Marin for DL: Downlink link interference factor, 2 dB by default;

3. Interference Marin for UL: Uplink link interference factor, 3 dB by default;

4. DU Building Loss: Building penetration loss of dense urban areas, 18 dB by

default. At present, the 2.5 GHz and 3.5 GHz systems at use the same DU

Building Loss.

5. U Building Loss: Building penetration loss of common urban areas, 15 dB by

default. At present, the 2.5 GHz and 3.5 GHz systems use the same U Building

Loss.

6. SU Building Loss: Building penetration loss of suburban areas, 12 dB by default.

At present, the 2.5GHz and 3.5GHz systems use the same SU Building Loss.

7. RU Building Loss: Building penetration loss of rural areas, 8 dB by default. At

present, the 2.5GHz and 3.5GHz systems use the same RU Building Loss.

8. Vehicle Loss: Vehicle loss, 6 dB by default. At present, the 2.5GHz and 3.5GHz

systems use the same Vehicle Loss.

9. DU Standard Deviation: Standard deviation of ground objects in dense urban

areas. The parameter describes the difference between the ground objects that

locate in the same distance but in different directions. The default value is 10

dB.

10. U Standard Deviation: Standard deviation of ground objects in common urban


locate in the same distance but in different directions. The default value is 8 dB.

11. SU Standard Deviation: Standard deviation of ground objects in suburban


locate in the same distance but in different directions. The default value is 6 dB.

12. RU Standard Deviation: Standard deviation of ground objects in rural areas.

The parameter describes the difference between the ground objects that locate

in the same distance but in different directions. The default value is 5 dB.

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WiMAX Planning

13. DU BS Antenna Height: Antenna height of outdoor base stations (BS) in dense

urban areas. The default value is 30 m.

14. U BS Antenna Height: Antenna height of outdoor BSs in common urban areas.

The default value is 30 m.

15. SU BS Antenna Height: Antenna height of outdoor BSs in suburban areas. The

default value is 35 m.

16. RU BS Antenna Height: Antenna height of outdoor BSs in rural areas. The

default value is 45 m.

17. SS Antenna Height: Antenna height of terminals. The parameter is configured

according to the actual scenario of the service area. In the case of the PCMCIA

or USB Dongle, the default value is 1.5 m. In the case of the fixed indoor CPE

and outdoor fixed CPE, need to set suitable value according application

scenario.

4.3.4.2 System Parameters Setting

1. Permutation: If the number of channel (carrier) is 1, the parameter may be set

to PUSC 1/3 or PUSC FFR in link budget. In other cases, the parameter is set

to PUSC Total by default.

2. FFT Size: Number of FFT size. The parameter is configured in budget link. In

the case of the 5 MHz system, the parameter is set to 512. In the case of the

7M and 10 MHz system, the parameter is set to 1024.

3. HARQ Gain for DL Traffic: The default value is 4dB.

4. HARQ Gain for UL Traffic: The default value is 4dB.

5. Map Repetition Times configuration: The default value is 4.

6. System Configuration: The parameter must be set to 2*2MIMO or 2*4MIMO or

4*8MIMO or 4*8BF.

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WiMAX Planning

7. Num. of Symbol DL, Num. of Symbol UL: The recommended default values of

the two parameters are 31 and 15 respectively. If other values are required, see

the contents in the Profile of the forum.

8. Num. of Symbol DL MAP: The default value is 4 or 6.And it is decided by map

repeat

9. Num. of Symbol Preamble: The parameter must be set to 1 as specified by the

standard.

10. Num. of Symbol DL Data: The parameter is calculated by the link budget.

11. Num. of Symbol UL Overhead: The default value is 3.

12. Num. of Symbol UL Data: The parameter is calculated by the link budget.

13. Num. of DL Subchannel: The parameter is selected by the link budget.

14. Num. of DL MAP Subchannel: The parameter is selected by the link budget

itself.

15. Num. of UL Subchannel: The parameter is selected by the link budget itself.

16. SBC Message PDU Size: This parameter will be a variable according to

different terminal capability, now the default value is 98bytes come from

Malaysia Packet One WiMAX network.

4.3.4.3 BS Parameters

1. BS Tx Power: Transmit power of a single antenna. The parameter is selected

by the link budget. In the case of the 2.5G system, the parameter is set to 40

dBm by default; in the case of the 3.5G system, the parameter is set to 39 dBm

by default.

2. BS Antenna Gain: The default value is 17.5 dBi;

3. BS Filter&Cable Loss: The default value is 1dB, this value is decided by RRU

install method.

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WiMAX Planning

4. BS Noise Figure: The default value is 4dB.

5. Num. of BS Tx and Rx Antenna: This value will be changed according to

system configuration automatic

4.3.4.4 Traffic Parameters

1. UL Data Rate at Coverage Edge: Required uplink data rate at the coverage

edge. The default value is 64 kbps.

2. UL Modulation Mode at Coverage Edge: Uplink modulation mode at the

coverage edge. The parameter must be QPSK or 16QAM.

3. UL Coding Mode at Coverage Edge: Uplink coding mode at the coverage edge.

The parameter must be CTC 1/2 or CTC 3/4.

4. DL Modulation Mode at Coverage Edge: Downlink modulation mode at the

coverage edge. The parameter must be QPSK or 16QAM.

5. DL Coding Mode at Coverage Edge: Downlink coding mode at the coverage

edge. The parameter must be CTC 1/2 or CTC 3/4.

6. DL and UL Allocated subchannels: This value is decided by bandwidth and

permutation method.

7. Limited subchannel number at coverage edge: This parameter will bring effect

to uplink cell edge data rate; maximum value can’t exceed the allocated

subchannel number.

4.3.4.5 Terminal Parameters

1. SS Type: The parameter is selected in link budget:

In the case of the mobile networking scenario, the parameter is

automatically set to PCMCIA Card or USB Dongle.

In the case of the fixed access indoor coverage scenario, the parameter is

automatically set to CPE. 49

WiMAX Planning

In the case of fixed access outdoor coverage scenario, the parameter is

automatically set to the outdoor CPE.

2. SS Tx Power: The parameter is selected in link budget:

In the case of PCMCIA Card or USB Dongle, the parameter is set to 23

dBm.

In the case of indoor CPE, the parameter is set to 26dBm.

In the case of outdoor CPE, the parameter is set to 26dBm;

3. SS Antenna Gain: The parameter is selected in link budget:

In the case of PCMCIA Card or USB Dongle, the parameter is set to 0 dBi.

In the case of indoor CPE, the parameter is set to 6 dBi.

In the case of outdoor CPE, the parameter is set to 15 dBi.

4. SS Filter&Cable Loss: The default value is 0.

5. Num. of SS Tx Antenna: The default value is 1.

6. Num. of SS Rx Antenna: The default value is 2;

7. SS Noise Figure: The value is 5dB for outdoor CPE, other terminal is 5.5dB.

4.3.4.6 Link Budget Table

The following is link budget (DU) table in typical configurations.

WiMAX Link Budget DL MAP DL Traffic Ranging UL INE UL

Traffic

Item Unit Value Value Value Value Value

Application Scenario - Nomadic Nomadic Nomadic Nomadic Nomadic

Coverage Level - Indoor Indoor Indoor Indoor Indoor

Frequency MHz 2500 2500 2500 2500 2500

TDD channel bandwidth MHz 5 5 5 5 5

FFT Size - 512 512 512 512 512

Permutation - PUSC PUSC PUSC PUSC PUSC

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WiMAX Planning

Total Total Total Total Total

TDD Channel Bandwidth MHz 5 5 5 5 5

Frequency Reuse - 1*3*3 1*3*3 1*3*3 1*3*3 1*3*3

Modulation Mode at Coverage

Edge - QPSK QPSK QPSK QPSK QPSK

Coding Mode at Coverage Edge CTC 1/8 CTC 1/2 CTC 1/2 CTC 1/2 CTC 1/2

System Configuration - 2*4MIMO 2*4MIMO - - -

Num. of Transmitting Symbol - 6 28 3 9 9

Repetition Time - 4.00 0.00 0.00 0.00 0.00

HARQ Time - - 3.00 - 3.00 3.00

Transmitter Side

Num. of Tx Antenna - 2 2 1 1 1

Tx Power per Antenna dBm 37.00 37.00 26.00 26.00 26.00

Multiple Antenna Combining

Gain dB 3.0 3.0 0.0 0.0 0.0

Tx Antenna Gain dBi 17.50 17.50 6.00 6.00 6.00

RF Filter + Cable Loss dB 1.00 1.00 0.00 0.00 0.00

Tx EIRP dBm 56.51 56.51 32.00 32.00 32.00

Receiver Side

MCS QPSK-1/2 QPSK-1/2 BPSK QPSK-1/2 QPSK-1/2

Channel bandwidth MHz 5.00 5.00 5.00 5.00 5.00

Subcarrier spacing kHz 10.94 10.94 10.94 10.94 10.94

Total pilot subcarriers 60.00 60.00 140.00 140.00 140.00

Total data subcarriers 360.00 360.00 280.00 280.00 280.00

Subcarriers per subchannel 28.00 28.00 24.00 24.00 24.00

Pilot subcarriers per slot 8.00 8.00 24.00 24.00 24.00

Data subcarriers per slot 48.00 48.00 48.00 48.00 48.00

Total subchannels 15.00 15.00 17.50 17.50 17.50

Allocated subchannels 15 15 6 6 3

Allocated subcarriers 420 420 144 144 72

Occupied bandwidth kHz 4593.75 4593.75 1575.00 1575.00 787.50

Thermal noise kT dBm/Hz -174.00 -174.00 -174.00 -174.00 -174.00

Rx Noise Figure dB 5.50 5.50 4.00 4.00 4.00

Noise floor (power) -101.88 -101.88 -108.03 -108.03 -111.04

Num. of Rx Antenna - 2 2 4 4 4

Required SINR at Antenna Port dB -1.80 3.10 -3.40 1.50 1.50

Rx Antenna Gain dBi 6.00 6.00 17.50 17.50 17.50

Rx Filter Loss + Cable Loss dB 0.00 0.00 1.00 1.00 1.00

Rx Sensitivity dBm -109.68 -104.78 -127.93 -123.03 -126.04

System Gain

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WiMAX Planning

HARQ Gain dB - 4.00 - - 4.00

System Margin

Shadow Margin for 90% Area

Rate dB 7.72 7.72 7.72 7.72 7.72

Interference Margin dB 2.00 2.00 3.00 3.00 3.00

Penetration Margin dB 18 18 18 18 18

Rx implementation Margin dB 5 5 3 3 3

Link Budget dB 133.47 132.57 128.21 123.31 130.32

4.4 Output Parameters

According to link budget table, we can get the MAPL and cell radius, and then

calculate the site number to meet coverage

4.4.1 Cell Radius Calculation

Combine the MAPL、BS and SS antenna height、suitable propagation model

parameters, we can conclude the cell coverage radius ,as following table shows:

WiMAX Link Budget DL MAP DL Traffic Ranging UL INE UL

Traffic

Item Unit Value Value Value Value Value

Coverage Radius Cal.

BS Antenna Height m 30 30 30 30 30

SS Antenna Height m 1.50 1.50 1.50 1.50 1.50

K1 - 168.32 168.32 168.32 168.32 168.32

K2 - 44.90 44.90 44.90 44.90 44.90

K3 - -2.55 -2.55 -2.55 -2.55 -2.55

K4 - 0.00 0.00 0.00 0.00 0.00

K5 - -13.82 -13.82 -13.82 -13.82 -13.82

K6 - -6.55 -6.55 -6.55 -6.55 -6.55

Radius of RF Coverage km 0.50 0.47 0.35 0.26 0.41

4.4.2 Site Number Estimation Based on Coverage Requirement

From the link budget table first sheet “RF Planning Input&Output”, could show the

following directly result.

Site Num. due to Coverage

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WiMAX Planning

DU Coverage Radius km 0.283

U Coverage Radius km 0.480

SU Coverage Radius km 1.681

R Coverage Radius km 5.336

DU Coverage Area per BS (Cloverleaf) Sq. km 0.156

U Coverage Area per BS(Cloverleaf) Sq. km 0.448

SU Coverage Area per BS (Cloverleaf) Sq. km 5.509

R Coverage Area per BS (Cloverleaf) Sq. km 55.476

DU Site Num. - 129

U Site Num. - 90

SU Site Num. - 19

R Site Num. - 4

Sum. Of Site Num. - 242

As one project RF planning, first planner should classify the whole coverage area

into different clutter types based on the digital map or google earth. Then statistic

the area for every kind clutter. The areas of the clutters in the service area are

divided by the corresponding single-BS area. Then, the results are rounded up and

summed to get the coverage requirement-based site number.

Site number=Roundup (clutter coverage area/BS coverage area,0)

How to calculate the BS coverage area?

The coverage areas of a single BS are calculated based on the predicated

coverage distance for different types clutter (DU, U, SU, and RU etc.) by using the

formula:

2389 ReaPerBSCoverageAr ××=

(cloverleaf)

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5 Chapter5 WiMAX Capacity Planning

Knowledge

Capacity Planning---------------------------------------------- ---------------------Level1 2

In addition to the coverage requirement, the network planning should also take the

capacity requirement into consideration. The planning result must meet the

coverage requirement and capacity requirement at the same time.

This chapter describes the subscriber predication, service models, and the

calculation of WiMAX capacity.

5.1 Principles of Subscriber Predication

Subscriber predication is an important factor in deciding the scale of mobile

communication construction. It determines the investment scale of engineering

construction and the economic benefits after commercial application.

The subscriber predication must take the following factors into consideration:

General development strategy of the country and city

Population distribution of the service area

Economic development level and prospect of involved areas

Requirements of local economic development on mobile telephony

Affordability of subscribers

Before the market requirement predication, related personnel must have an exact

understanding on the development rules of cellular mobile communication and the

current development phase that cellular mobile communication is in.

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WiMAX Planning

The development of cellular mobile telephony complies with the growth curve. In

the initial phase, the price of mobile telephony is expensive and the increase of

absolute subscriber number is slow. However, due to the small base, the growth

rate is very high. With the decrease of equipment costs, mobile telephony is

gradually recognized and accepted by people and the cellular mobile telephony

enters the exponential development phase. Then, the mobile telephony enters the

stable development phase and finally to the saturation phase. Figure5-1 shows the

growth curve of the cellular mobile telephony.

Figure 5-1 Growth curve of cellular mobile telephony

Popular rate

Stable development phase

Exponentialdevelopment phase

TimeStar

Based on analysis, the cellular mobile communication of China is in the high speed

growth phase, which is featured by high growth rate.

The environment for the development of cellular mobile communication in the next

few years has the following characteristics:

1. The economy maintains a high growth rate and the Chinese people steps

into the well-off phase.

2. The ratio of expense on communication to the total personal income is

increasing.

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WiMAX Planning

3. The personnel flowing are increasing and the requirements on mobile

communication are enhanced as a result.

4. The competition is becoming more and more severe.

5. The costs of communication equipment, including mobile phones, are

decreasing.

6. The communication tariff is regulated downwards.

7. The diversity of services is increasing.

8. The QoS of network keeps on improving.

9. Personal subscribers become the main body of the communication

market.

It can be predicated that, the cellular mobile telephony market will grow a high rate

in a period and will gradually develop to the stable development phase.

5.2 Service Models

WiMAX network can supply both mobile service and fix bandwidth service, 3 types

are defined as below:

1. mobile subscribers, such as data card customer including inside design

and outside design ,the service can access network in anywhere and

anytime, the data service can mobile and handover, the terminal

include PDA, UMPC and laptop

2. family subscribers, the terminal include indoor modem, outdoor modem

and computer card

3. corporation subscribers, supply network service and customized service

for corporation, the terminal include indoor modem, outdoor modem and

customized CPE

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WiMAX Planning

The WiMAX Forum has identified several applications for 802.16e-based

systems and is developing traffic and usage models for them. These

applications can be broken down into five major classes. These application

classes are summarized in the following:

WiMAX AWG Class Packet Data Applications

Class1 Interactive Game Qake II,World of Warcraft

Class2 VoIP and Video conference VoIP, Video conference, PTT

Class3 Streaming Media

Music/speech, Video Clip, Movie, Streaming,

MBS

Class4 Basic Internet Applications Web Browsing, E-mail

Class5 File transfers, Media Download FTP, P2P

WiMAX Forum Application Working Group (AWG) defines application session and

sub-session.

Application Session Sub-session

Internet Game Internet game start to end N/A

VoIP A voice call N/A

Video Conference Video conference start to end N/A

Push-to-Talk(PTT) A voice call consist of multiple talk opportunities Each opportunity to talk

Music/Speech An access music service consists of multiple audio media

play

Each audio media

Video Clip One Video Clip send or receive N/A

Video Streaming Video play start to end N/A

MBS MBS service start to end and it may consist of multiple

sub sessions

Each service channel

IM A set of message exchange Each message send or receive

Web Browsing Web browsing start to end and it may consist of browsing

multiple web pages

Each web page

Email Email application start to end and it may consist of

multiple email send or receive

Each email send or receive

Telemetry Each message send or receive N/A

FTP Each file send or receive N/A

P2P P2P application start to end N/A

5.3 WiMAX Traffic Model

The data service requirement of a WiMAX system is related to the following factors:

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WiMAX Planning

Name Unit

NT Number of total subscriber

FO Online subscriber ratio %

NO Number of online subscriber

Oversubscription Online and active subscriber ratio in total subscriber %

Active ratio active subscriber ratio in online subscriber %

NOA Online and active subscriber

Subratio Service Subratio %

DLav Average DL throughput kbps

ULav Average DL throughput kbps

D Average session duration s

G Active link ratio in one session %

H Busy hour sessions per subscriber

DLact Average active DL throughput kbps

ULact Average active UP throughput kbps

NOA = NT* Oversubscription

NOA = NO * Active ratio

Oversubscription = FO * Active ratio

The voice service can also be converted in the data service as the VoIP service.

Table 5-1 Default configurations of the WiMAX traffic model

Average Rate/Service

(kbps)

Average Rate/User

(kbps)

User Type Ratio

Service

Type Sub ratio

Oversubscri

ption DL UL DL UL

Internet 100% 20 1024 128 46.08 5.76

VoIP 50% 6 44.8 44.8 3.36 3.36

Video 15% 20 128 16 0.86 0.11

Residential 90%

Leased

Lines 1% 1 256 256 2.30 2.30

Internet1 50% 10 1024 128 5.12 0.64

Internet2 50% 10 1024 128 5.12 0.64

VoIP 100% 6 44.8 44.8 0.75 0.75

Video 15% 20 128 16 0.10 0.01

Business 10% Leased 1% 1 256 256 0.26 0.26

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WiMAX Planning

Lines

Final Average Data Rate Requirement /User kbps 63.95 13.83

It can be seen from Table5-1 that, the downlink data rate requirement per

subscriber in the WiMAX system is 63.95 kbps and the uplink data rate requirement

is 13.83 kbps.

5.4 WiMAX Capacity Planning

The WiMAX capacity planning is described by using the 10 MHz system as an

example, in which, the frame duration is 5ms. Suppose 31 symbols are allocated to

the downlink subframe and 15 symbols are allocated to the uplink subframe.

According to the introduction to the frame structure, the downlink subframe needs

the overhead of three symbols, of which, one is allocated to the preamble and the

other two are allocated to FCH and DL MAP. The uplink subframe needs the

overhead of three symbols for ranging.

Total number of slots of the downlink subframe: 4202/)331(*30 =− ;

Total number of slots of the uplink subframe: 1403/)315(*35 =− ;

The downlink subframe also carries the UL MAP. Suppose the UL MAP occupies

30 slots (30 subchannels and 2 symbols).

Besides, the DCD/UCD period is 2s (400*5ms). Hence, if the DCU/UCH overhead

is allocated to the slots occupied by each subframe, namely 90/400, the overhead is

negligible.

5.4.1 Physical Layer Traffic Calculation of Downlink

The physical layer traffic of the downlink subframe in different modulation and

coding modes is as follows:

QPSK 1/2: DL Throughput= (420-30)*48*200=3.744Mbps

QPSK 3/4: DL Throughput= (420-30)*48*200*3/2=5.616Mbps

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WiMAX Planning

16QAM 1/2: DL Throughput= (420-30)*48*200*2=7.488Mbps




64QAM 3/4: DL Throughput= (420-30)*48*200*4.5=16.848Mbps


If the 2×2MIMO (SM mode) is used, the traffic is doubled.

5.4.2 Physical Layer Traffic Calculation of Uplink

QPSK 1/2: UL Throughput=140*48*200= 1.344Mbps

QPSK 3/4: UL Throughput=140*48*200*3/2= 2.016Mbps

16QAM 1/2: UL Throughput=140*48*200*2= 2.688Mbps

16QAM 3/4: UL Throughput=140*48*200*3= 4.032Mbps

If the 2×2MIMO (SM mode) is used, the traffic is doubled.

5.4.3 BS Throughput Calculation Principle

Above table the BS throughput value is only based on the maximum throughput

theory calculation. For the commercial network, not every site could achieve the

throughput value. So we define the ratio for different scenario.

Ratio Value

Typical DL Ratio 0.55

Typical wave1 UL Ratio 0.8

BF DL Ratio 0.85

BF UL Ratio 0.8

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WiMAX Planning

So the actual capacity of 5M system, 7M system and 10M system is as below:

5MHz Bandwidth 10MHz Bandwidth

TDD Ratio Wave 1 SIMO

1X2

Wave 2 MIMO

2X2

Wave 1 SIMO

1X2

Wave 2 MIMO

2X2

DL 11.52 23.04 23.04 46.08 In Theory

UL 1.47 2.61 3.02 5.38

DL 6.34 12.67 12.67 25.34 35:12

Typical UL 1.18 1.70 2.42 3.50

DL 10.08 20.16 20.16 40.32 In Theory

UL 1.96 3.92 4.03 8.06

DL 5.54 11.09 11.09 22.18 31:15

Typical. UL 1.57 2.55 3.22 5.24

DL 9.36 17.28 18.72 34.56 In Theory

UL 2.45 4.90 5.04 10.08

DL 5.15 9.50 10.30 19.01 29:18

Typical UL 1.96 3.19 4.03 6.55

DL 7.92 14.40 15.84 28.80 In Theory

UL 2.94 5.22 6.05 10.75

DL 4.36 7.92 8.71 15.84 25:21

Typical UL 2.35 3.39 4.84 6.99

As the beamforming BS actual throughput as following table:

Beamforming Sector Throughput

TDD Ratio 5MHz BF 10MHz BF

DL 8.57 17.14 31:15

UL 1.71 3.43

DL 7.34 14.69 29:18

UL 1.96 3.92

7 MHz Bandwidth

TDD Ratio Wave 1 SIMO 1X2 Wave 2 MIMO 2X2 BF

DL 12.96 23.07 12.96 In Theory

UL 3.02 5.38 3.02

DL 7.13 12.69 11.02 21:12

Typical UL 2.42 4.30 4.30

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6 Chapter6 Site Survey and Planning

Knowledge point

Overview-------------------------------------------- ---------------------Level 1 2

Introduction-------------------------------------------------------------- Level 1 2

Site Survey----------------------------------------------------------------Level 1 2

6.1 Overview

This chapter describes the principles of surveying available sites, planned sites,

and ultra-wide coverage sites.

The contents in red in Figure6-1 shows the position of site survey in network

planning.

Figure 6-1 Position of site survey in network planning

Project pre-investigation

Available sitesurvey

Requirementanalysis

Planned sitesurvey

Site distributionplanning

Wirelessenvironment test

Networkevaluation

Wireless networkdesigning report

output

PN planning andneighboring cell

configurationEmulationPlanning result

confirmation

Proceduretailoring

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WiMAX Planning

6.2 Introduction to Site Survey

The network planning involves the survey of available sites and planned sites. The

information of available sites is obtained in the requirements analysis phase by

communication with the operator, and the information of planned sites can be

obtained during site planning stage.

The survey of available sites can be implemented in other phases than in available

site survey phase and depends on the understanding of the project manager on the

land form and topography of the planned area. In some cases, engineers need to

survey only the available sites in key locations. Whether the survey of available

sites in other locations is necessary is decided in the planned site survey phase.

The available sites of the operator that meet the requirements of the network

topology are selected as the preferred candidate sites in the planned site survey

phase.

The operator provided sites survey is not always done during available sites survey

stage, we can determine whether survey is needed for part or all available sites

based on project manager’s knowledge of the planned environment. It is possible

that we just make survey of some important sites, as the base of network topology,

the other available sites are left for determine whether need survey during planned

sites survey stage. The available sites provided by operator which meet the network

topology requirements will be set as the primary sites during planned site survey

stage.

For the network planning in rural/road areas, the available sites of the operator are

scattered in different locations. It is difficult to survey all the available sites in the

available site survey phase. In this case, the project manager can establish the

network topology based on the distribution of available sites and the available site

survey can be carried out in the planned site survey phase. The project manager

should select other sites only when the available sites of the operator fail to meet

the requirements.

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WiMAX Planning

6.3 Site Selection Principles

Before conducting the site survey during the network planning, it needs to select

appropriate sites among the sites provided by the customer and those planned sites.

Here list the basic requirements for qualified sites:

1. Orientation: The sector orientation cannot be blocked by obvious barrier,

which may result in coverage failure in some areas.

2. Height: The antenna height of an urban site should be 10~15 m higher

than the surrounding objects and that of a suburban site should be 15 m

higher than the surrounding objects, whose height is determined

according to the required coverage range. In terms of the planned sites

station, the height of surrounding buildings must not over 1.3 times than

that of the planned antenna height.

3. Interference: avoid interference from other systems exists. Select the

sites where there is no interference or the problem of existing interference

can be solved.

4. GPS: The GPS solid angle cannot be less than 90 degrees. The surface

area of the antenna visible in the GPS installation location cannot be less

than 1/4 of the surface area of the globe (4πR2), namely πR2.

5. Antenna feeder: The space on the top of the building or tower is enough

for the installation of antenna feeders.

6. Basic condition: Positions, transmission, and power supply are available

for equipment installation.

7. Site selection: the distance between the actual location and planned

location of the site station cannot exceed one fourth coverage radius.

An available site can still be selected as a normal site if it meets the preceding

requirements after improvement. For example, if the antenna height is lower than

the required value, the site is still qualified as a normal site providing that the

antenna height can be increased in certain means. If there exist barriers in some

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WiMAX Planning

direction, the sector in this direction can be cancelled under the condition that the

network topology will not be affected etc.

The following contents describe the first three requirements in detail.

6.3.1 No Obvious Blocking Objects around the Site

Blocking affects the coverage of the areas behind the blocking objects and may

lead to coverage dead zone. The blocking objects in the sector orientation can

reflect signals and thus affect the coverage of the areas behind them. Hence,

serious blocking in the sector orientation must be avoided.

Barriers have great influence on the coverage. They may result are such problems:

in the back area of the barrier a shadow always occurs, which easily produces blind

coverage area; the signal is easily reflected by barriers, which will bring co-channel

interference to the opposite direction ,and so on.

The distance between a blocking object and the site should be calculated in

compliance with the following principles:

The vertical field angle corresponding to the blocking in the vertical direction has the

largest effect on the coverage. The distance between the blocking object and the

site is calculated as follows (supposing the diffraction capability is strong enough):

1. In the case of a blocking object much higher than the sector, suppose the

vertical field angle is α, the blocking object is H higher than the building,

and the distance between the blocking object and the base station is L,

then, L must meet the following requirements:

L > H/(tgα/2);

For example, if the vertical field angle is 7° and the height difference is 20 m, the

distance must be greater than 330 m.

2. In the case a small blocking object, to avoid serious obstacle, the distance

L from the barrier to the site must meet the following requirements:

L > 2*λ*(180/(α*π))2; 66

WiMAX Planning

In which, λ is the wavelength.

6.3.2 Site Height

The planned antenna height of urban sites must be 10~15 m higher than the

average height of the objects around the building and that of rural and suburban

sites must be 15 m higher than the average height of the objects around the site. In

very densely urban area, the antenna height can be about 10meters higher.

If the site in a dense area is too high, such as more than 20 m higher than the

objects around it, the signal radiation range will be too wide and may cause

interference with adjacent sites. If the antenna height reaches up to 60 m, the

indoor areas around the bottom of the base station cannot be covered and become

a blind coverage area.

In contrast, if the site is too low, such as less than 10 m higher than the objects

around it in the suburban area, the coverage area will be too small and cannot meet

the coverage requirement. Generally this problem can be solved by heightening the

antenna such as increase the pole, mount or rack; but one thing need to be

guaranteed, the site location must possess the bearing ability for antenna

heightening.

In the case of low sites required by the operator, such as the equipment room

building or parent exchange, if the transmission and power supply are available and

the site is not obviously blocked, the site height can be increased by lengthening

the pole or tower.

6.3.3 Avoid Interference with Other Systems

If the available candidate sites include the sites of other systems and their

conditions are close to other candidate sites, the co-site should be considered,

except that the land forms around the sites change greatly, such as serious

blocking, small antenna height, no equipment room, and antenna installation

difficulty. The co-site brings many advantages, such as convenient isolation, easy

leasing, and availability of equipment room, transmission, and power supply.

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WiMAX Planning

Like co-site scenario, the WiMAX system may interfere in other systems and can

receive the interference from other system. This problem should be taken into

consideration during the network planning.

If WiMAX system needs to share a site with other system, in this case, the isolation

requirement can be met in vertical isolation mode. The WiMAX antenna can be

installed on the top of an antenna of another system or in a plane in the same

direction. Likewise, horizontal or vertical isolation can also be used to reduce the

interference between WiMAX and other system. But how far the isolation distance

need to be calculated by the specific equation, we should clear about the interfered

and interfering some parameters like system frequency, antenna gain, out-band

spurious, RX noise power and isolation requirement etc.

In addition to the isolation from other systems, the isolation from other equipment

with similar frequencies should also be considered. The base station cannot be

installed near large-power radio stations or paging and microwave equipment with

similar frequencies.

In the WiMAX system, the interference between sites is very serious, especially

when the sectors of two sites are installed face to face. Hence, a certain space must

be maintained between two sites. The selected site must keep a distance from

adjacent sites with close frequencies.

6.4 Ultra-Wide Coverage Site Survey and Selection

The networking planning of ultra-wide coverage is different from the common

network planning. The network planning of ultra-wide coverage must handle the

pilot pollution in remote areas and the effects on the current network. Hence, the

sites in the network planning must be selected in a different way.

The network planning process of ultra-wide coverage is as follows:

1. Get the requirements, including the required coverage range and other

information.

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WiMAX Planning

2. Estimate the antenna height required for the coverage according to the

ultra-wide coverage model.

3. Test and simulate the coverage of existing networks in the required

coverage area.

4. Design the network topology based on the electronic map in combination

with the coverage of existing networks and the required antenna height,

including the site location, orientation, and antenna parameters. The pilot

pollution in remote areas must be considered in the design.

5. Carry out field survey and select qualified sites. The selected site must

meet the requirements on height and sector orientation and should cause

minimum effect on the inland. If the site survey is implemented in a high

location, the site selected should be lower than the peak. In this way, the

mountains and other ground objects provide certain blocking functions

against the sites behind them and thus the effect on existing networks is

minimized.

6. Verify the survey results by simulation and survey the problematic sites

again.

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7 Chapter7 Antenna Selection

Knowledge point

Overview------------------------------------------------------------------Level3 4

Antenna Selection------------------------------------------------------- Level3 4

Indoor Antenna-----------------------------------------------------------Level3 4

7.1 Overview

During the network planning and optimization, the selection for antennas is an

important work. Proper antennas can not only improve network coverage and

capacity, but also shorten the time of network planning and optimization, and save

human and physical resources.

This manual is to guide antenna selection in network planning process. It can also

be used in the network optimization stage to aid judging whether the selected

antennas are suitable or not.

7.2 Antenna Selection

There are many parameters involved in antenna selection, mainly including

frequency range, polarization mode, radiation pattern, gain, horizontal BW (beam

width), vertical BW, downtilt mode, side lobe suppression, null fill, front-to-back ratio,

maximum input power, third-order inter-modulation, isolation, input impedance, and

mechanical specifications, etc. Among them, the radiation pattern, gain, horizontal

BW, vertical BW and downtilt mode should be determined according to the

coverage area’s characteristics such as terrain and clutter, base station height and

coverage radius. And the selection of other antenna parameters is relatively simple

and they can be decided on the basis of the characteristics of the system being

designed.

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WiMAX Planning

In the following Chapter, we will introduce the basic methods and considerations for

selecting antennas through explaining the key parameters of the antenna.

7.2.1 Frequency Range and Polarization Mode

The frequency range of the antenna needs to correspond with that of the network.

In order to minimize the effect of out-band interference, the antenna’s frequency

range is expected to just fall into the system’s frequency band.

Base station antennas usually adopt linear polarization. Among them,

single-polarization antennas usually adopt vertical polarization, and

dual-polarization antennas usually adopt 45º linear polarization. A dual-polarization

antenna is composed of two orthogonally polarized antennas which are installed

inside the same radome. Using dual-polarization antennas can decrease the

quantity of antennas, simplify antenna installation, cut down engineering cost and

reduce antenna occupation.

In urban areas, base stations are relatively many in number and the coverage

radius of each base station is small. To facilitate antenna installation and

considering that base stations have high probabilities to be adjusted in the future,

base stations are recommended to adopt dual-polarization antennas.

In suburban and rural areas, there are much fewer base stations and the coverage

radius of each base station is large. Single-polarization antennas with space

diversity are recommended since space diversity can enhance the receiving effect

of the base station.

7.2.2 Radiation Pattern, Horizontal BW, Vertical BW, and Gain

According to the radiation pattern, base station antennas can be divided into omni

directional antennas and directional antennas. Omni directional antennas radiate

equally in all directions of space, and are suitable for the coverage of omni cells.

The radiation of directional antennas is concentrated in some certain direction, so

they are applicable for the coverage of sectored cells.

On the horizontal plane (or vertical plane) of antenna radiation pattern, the angle

between the two points at which the antenna gain is 3 dB lower than the maximum

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power point on the main lobe is called antenna’s horizontal/vertical beamwidth (BW).

In some literatures, they are also called horizontal/vertical lobe width or

horizontal/vertical lobe angle. Most of the energy radiated by the antenna falls into

the lobe width, and the size of the beamwidth implies the concentration level of

antenna radiation. The horizontal BW of the omni directional antennas is 360º; and

the horizontal BW of directional antennas can be 20º, 30º, 65º, 90º, 105º, 120ºor

180º, among which 65º and 90º are commonly used. Typically, the vertical BW of

antennas is between 3 º ~ 80 º and antennas with 5 º ~ 18 º vertical BW is usually

used by base stations. The antenna gain is closely related to the horizontal and

vertical BW, and in general, the smaller the antenna beamwidth is, the larger the

gain. Therefore, when determining these three parameters, it needs to consider

them together.

To fit for various propagation environments and detailed terrain & clutter, it needs to

select antennas with different horizontal BW, vertical BW and gain, and the

following principles can be referred to when determining such three parameters:

1. Horizontal BW: determine the horizontal BW according to the shape of the

area to be covered; in the case that base stations are in large scale with

their coverage radiuses being small, and the traffic there is heavy, small

horizontal BW antennas should be selected. For the areas where the

coverage radiuses of base stations are relatively large and the traffic is low,

large horizontal BW antennas can be applied.

2. Vertical BW: in the areas where the terrain is flat, and buildings are

distributed sparsely and have a low average height, small vertical BW

antennas are applicable. For the areas whose terrain is complex and with

big fall, large vertical BW antennas are usable. In an area where buildings

are located densely and with a relatively high height, if the antenna is

mounted lower than the average height of surroundings, an antenna with

large vertical BW should be adopted; and if the antenna height roughly is

equal to or higher than its surroundings, an antenna with small vertical BW

can be selected.

Next, we will provide some detailed proposals on antenna selection for several

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1. Urban Area

For S111 type of base stations, antennas with 65º horizontal BW and 7º~10º

vertical BW are usually adopted, and the antenna gain is between 15~18 dBi.

For S110 or directional single-sector sites, based on the actual situation,

antennas with 65º, 90ºor even larger horizontal BW can be selected; and the

selection of their vertical BW and the gain can be conducted according to the

proposals for antenna selection of S111 sites. For omni directional sites,

antennas with small gain and adjustable electrical downtilt are often used.

2. Suburban and Rural Area

For directional base stations, antennas with 90ºhorizontal BW and 5º~7

ºvertical BW are applicable, and the gain of antenna is between 15~18 dBi.

For omni directional base stations, antennas with 5º~ 7º vertical BW are

preferable, and the gain of antenna is within 9~12 dBi.

3. Water Surface (Large Lake, Ocean), Gobi and Desert

Directional base stations: if the area to be covered is very wide, antennas with

90º or 105ºhorizontal BW and 5º~7º vertical BW can be selected, and the

antenna gain is within 14~18 dBi. Under the case of super-far coverage with

multiple base stations, if the near areas have been covered and the distance

between neighbor base stations are not far, considering to reduce handoff

areas and making the coverage as far as possible, antennas with 65ºcan be

used. If the expected coverage area is long but not very wide such as long and

narrow lakes, antennas with 65ºvertical beamwidth can be adopted.

For omni directional base stations, they can adopt antennas with 5º~7º vertical

BW, and the gain of antenna is within 9~12 dBi.

4. Long and Narrow Coverage Areas such as Highways, Railways, etc.

The antennas for covering highways and railways are determined according to

the length and shape of the area to be covered. If the road stretches straight,

high-power antennas with 20º~30º horizontal BW and 5º~7º vertical BW can

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be used. If the road bends greatly, antennas with 65º or 90º or even larger

horizontal BW and 5º～7º vertical BW are preferable to be used.

5. Area with Complex and Great-fall Terrain

In some cases, areas with great-fall terrain are encountered in network

planning. And such case further includes two types of situations: 1) when the

mounted antenna is higher than the average height of the coverage area,

antennas with vertical BW of 10º～18º can be used; 2) when the fall of the

local terrain is very great and most of coverage areas are higher than the

mounted antenna, an antenna with vertical BW of 18º～30ºcan be adopted, as

shown in the Figure 7-1.

Figure 7-1 Antenna Selection in a Coverage Area with Great-fall Terrain

6. Under Low Frequency

The dimension of an antenna is closely related to its frequency range. To

achieve the same vertical BW, an antenna with a low frequency band must

have the dimension much larger than an antenna with a high frequency band.

For a system with low frequency range such as a 450 MHz network, the

horizontal BW of the antenna can be selected according to the principles

introduced previously, and the range for the vertical BW can be widened on

the basis of above selecting principles. In urban areas with densely distributed

base stations and severe interference, if according to the general principles an

antenna with small vertical BW is to be selected, but in practice only another

antenna with large vertical BW is available, then an antenna with electrical

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7. The Base Station is Located Very High

Under such condition, antennas with large front-to-back ratio should be used,

so as to avoid great influences produced by antenna side lobes to the

surrounding environment.

7.2.3 Downtilt Mode

In order to reduce coverage holes and decrease the interference of the local base

station to adjacent base stations, avoid installing antennas very high; meanwhile,

antennas should be down tilted properly.

In urban areas, densely distributed base stations are apt to produce mutual

interference. For any one of base stations, in order to guarantee most of the energy

radiated from the antenna cover within the desired area and reduce the interference

exerted to adjacent base stations, make the half-power beamwidth at the antenna

main lobe point to the boundary of the coverage area. And here is the calculation

formula for the downtilt angle:

α = arctg (2H / L) * 180 / π + β/2 – e_γ

In some environments, such as suburban and rural areas, highways, sea surface,

etc., in order to make the coverage reach as far as possible, the initial downtilt can

be reduced and the maximum gain on the antenna main lobe can be let to point to

the boundary of the coverage area, and the formula for calculating the downtilt is as

follows:

α = arctg (H / L) * 180 / π + β/2 – e_γ

In above two formulas, α indicates the initial mechanical downtilt of the antenna, in

units of degree. H indicates the effective height of the base station, i.e. the

difference between the height of mounted antenna and the average height of the

surrounding coverage areas, in units of meter. L indicates the distance from the

antenna to the boundary of this sector, in units of meters. β Indicates the antenna’s

vertical BW, in units of degree. And e_γ indicates the electrical downtilt of the

antenna, in units of degree.

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The mechanical downtilt calculated with the above formulas is just an initial value

which can be used for network simulation and the setting of the initial downtilt of the

antenna. And this downtilt can be adjusted according to the simulation result or the

drive test result after the network is commissioning.

The antenna downtilt mode includes mechanical downtilt and electrical downtilt,

and the latter can be further divided into fixed and adjustable electrical downtilt.

Mechanical downtilt antennas are relatively cheap and only down tilted at

installation. They are mainly applied in conditions with downtilt angle less than 10º.

Though electrical downtilt antennas are relatively expensive, their downtilt angles

can vary in a larger range (can be over 10º); when the downtilt angle increases, the

antenna radiation pattern will not be distorted and the back lobe will tilt downwards

accordingly. For a situation requiring large downtilt angle, a fixed electrical downtilt

antenna with small angle plus mechanical downtilt is the mainstream solution.

The conditions requiring antennas with electrical downtilt mainly include:

For an urban site which is required to cover a small area with large

antenna downtilt, it is proper to adopt electrical antenna in order to

decrease the interference to other sites as much as possible.

For an urban site located high, it is preferred to utilize electrical

large-downtilt antenna or adjustable electrical antenna with upper side

lobe suppression and first lower null fill so as to decrease interference to

adjacent sites as much as possible.

For a site located high relative to its surroundings, such as a site on a

mountain or near a river, an antenna with electrical downtilt can be

selected.

Since omni directional antennas cannot mechanically down tilt, so for an

omni site at a very high position, an antenna with particular electrical

downtilt should be selected according to the detailed condition.

Under other conditions which need antennas with large downtilt, the

antennas with electrical downtilt can be adopted.

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7.2.4 Side Lobe Suppression and Null Fill

The coverage of signals is guaranteed mainly by the main lobe and the side lobes

below the main lobe of the antenna. While the side lobes above the main lobe can

not only waste the radiated energy, but also produce interference to adjacent base

stations, especially to the buildings in these adjacent base stations. Therefore, the

energy radiated through these upper side lobes should be suppressed as much as

possible, particularly the large first side lobe. At the same time, it also needs to fill

the null point below the main lobe, and the formula to calculate the null fill is as

follows:

Value of null fill = (Power level of the first vertically lower null fill / power level of

maximum radiation direction) % = 20 log (Power level of the first vertically lower null

fill / power level of maximum radiation direction) dB

The power level of the first upper side lobe above the main lobe should be less than

-18 dB.

The power level of the first lower null fill below the main lobe should be higher than

-20 dB, and if the value can reach -12 dB, it would be very ideal.

Figure 7-2 The Pattern Diagram of Radiation Range

7.2.5 Front-to-back Ratio, Maximum Input Power, Third-order Inter-modulation, Isolation

The antenna’s front-to-back ratio refers to the ratio of power level of the antenna’s

main lobe to the back lobe. Its value should be normally higher than 25 dB. 77

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The antenna’s maximum input power refers to the maximum RF transmit power

after the carriers are combined and then input into the antenna’s port. In the

practical determination, the value should be added with some proper margin on the

basis of this estimated value, and it normally should not be less than 150W.

The value of antenna’s third-order inter-modulation should be lower than -150

dBc@2×43dBm.

The isolation between any two of antenna’s ports should be higher than 30 dB.

The antenna’s VSWR should be less than 1.5.

7.3 Selecting Antennas for Indoor Distribution Systems

Generally speaking, the antenna for an indoor distribution system should comply

with the following two principles:

The antenna, on one hand, can satisfy the indoor coverage requirement; on the

other hand, will radiate outdoors as little as possible, so as not to interfere with

outdoor service areas.

The antenna should have a good appearance, and its shape, color and dimension

should be in harmony with the indoor environment.

The antennas for indoor distribution systems are mostly of small gain, and here are

their major types:

1. Ceiling-mounted Antenna

The ceiling-mounted antenna is a kind of omni directional antenna, and is

mainly installed on the ceilings of rooms, halls, corridors, etc. The gain of the

ceiling-mounted antenna is generally within 2~ 5 dBi, its horizontal BW is 360º,

and its vertical BW is about 65º.

The ceiling-mounted antenna has a good appearance. Being installed on the

ceiling, it emits the radio wave with even field strength in all directions. So

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when selecting the antenna for the indoor distribution system, the

ceiling-mounted antenna is preferable. The ceiling-mounted antenna should

be installed at the center of the ceiling rather than at a location such as near a

window or door from which the signals easily leak and interfere outdoors.

2. Wall-mounted Panel Antenna

This is a kind of directional antenna, and often installed on the walls of rooms,

halls and corridors. The wall-mounted antenna has the gain of 6~10 dBi that is

higher than that of the ceiling-mounted antenna. Its horizontal BW may have

multiple angles, such as 65ºand 45º. And its vertical BW is about 70º.

The wall-mounted antenna has a good look. With a relatively large gain, it is

always used in the long and narrow indoor environments. No obstacle should

stand in front of the antenna, and the antenna should not be installed just

opposite a location from which the signals are likely to leak outdoors such as

near a window or door.

3. Yagi Antenna

The Yagi antenna is a kind of directional antenna with large gain. It is mainly

used for covering narrow areas such as elevators. The gain of the Yagi

antenna is generally within 9~14 dBi.

4. Leaky Cable

The leaky cable can be considered as a kind of antenna. Through a series of

outlets cut in the outer conduct layer of the cable, the signals can be

transmitted and received along the cable. The leaky cable can be applied for

the coverage in tunnels and railways.

5. Other Antennas

Other antennas for indoor distribution systems also include spiral antennas,

pole antennas, and so on, whose gain is normally 2~3 dBi. Because their

appearances are not very good, they are rarely used.

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8 Chapter8 WiMAX Parameters Planning Knowledge point

Overview-------------------------------------------- --------------------- Level3 4

Frequency Planning------------------------------------------------------ Level3 4

Preamble Planning------------------------------------------------------- Level3 4

Neighbor Planning--------------------------------------------------------Level3 4

8.1 Overview

This document introduces the basic principles for WiMAX frequency planning 、

preamble planning and initial neighbor planning, which should be carried out during

the proposal output stage.

Figure 8-1 Network Planning Flow

8.2 Preamble & Neighbor Planning Flow

8.2.1 Frequency Planning Flow

Frequency planning flow is shown as the following Figure.

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Figure 8-2 Frequency Planning Flow

8.2.2 Preamble Planning Flow

Preamble planning flow is shown as the following Figure.

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Figure 8-3 Preamble Planning Flow

8.2.3 Neighbor Planning Flow

Neighbor planning flow is shown as the following Figure.

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Figure 8-4 Neighbor Planning Flow

8.2.4 Frequency Planning

As limited by the frequency resources, the frequency should be reused for the high

frequency efficiency. The frequency planning is to allocate the frequency to reduce

the co-channel interference. In order to conquer the interference within system, it

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should be ensured the distance between each two frequency reused as enough as

possible.

The Frequency Reuse Scheme (FRS) is defined by the number of BS per cluster,

number of sector per BS, number of frequency channels and optionally number of

segments. When the number of segments is not included it should be assumed

none. Some possible configurations are listed below.

- FRS=4, 12, 3- This is a low interference configuration

- FRS=1, 3, 3- This is a high interference configuration.

The next Figures illustrate these regular frequency reuse patterns.

Figure 8-5 FRS=4, 12, 3

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Figure 8-6 FRS=1, 3, 3

8.3 Preamble Planning Procedure

As defined in IEEE 802.16e standard, for the 1024 FFT system, preamble index

should be allocated by this way:

Preamble index 0~31 should be allocated to segment 0;



For preamble index 96+N (0<= N <= 17)

Preamble index 96+N0 should be allocated to segment 0, while N0 = 3k, k = 0,

1, 2…

Preamble index 96+N1 should be allocated to segment 1, while N1 = 3k+1, k =

0, 1, 2 …

Preamble index 96+N2 should be allocated to segment 2, while N2 = 3k+2, k =

0, 1, 2 …

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Usually, we use preamble index 0~95 to preamble plan, 96~113 are reserved

for future capacity extension or for conquering interference.

Since there are only 114 preamble indexes available, preamble reuse should

be taken into consideration, especially for a system with many base stations.

Usually, base stations should be divided into several clusters, which should be

planned with one preamble reuse set.

In order to conquer the interference within system, it must be ensured enough

distance between each two preamble index reused.

According to the two factors above, a cluster contains 19~32 base stations

is recommended.

8.4 Neighbor Planning Procedure

Once preamble planning has been approved, network planning engineer could go

on with initial neighbor list planning, which influences the network handover

performance most at the beginning of service.

Figure 8-7 Initial Neighbor List Planning

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Before the network starts to service, the initial neighbor list could be planned by the

following principles, and it should be adjusted again according to the handover

times statistic got by OMC.

1. All the cells belong to a same BS must be configured as neighbor each

other;

2. Cells in the first and the second layer could be configured as neighbor

according to coverage planning. Generally, cells which are against the

planning cell should be configured as its neighbors, while cells in the first

layer. should be configured each other

3. Here is an example of neighbor planning, the red solid array stands for the

cell to be configured, and the dotted arrays stand for its neighbors.

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Once every cell has be assigned neighbors, ZXPOS CNO could be used again to

check out whether the neighbors are interworking, and made further adjusting. For

detailed operation, please refer to Chapter 9.4.

The maximum neighbor number per cell could be no more than 10.

After the whole network was built and on air, we should according DT test result to

adjust the neighbor cell list and priority.

8.5 ZXPOS CNO1 Planning Introduce

With the ZXPOS CNO1, we can completely finish the frequency, preamble and

neighbor planning.

1. Import the site information sheet.

2. Show the sites

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3. Frequency and Preamble plan

4. Set the parameters

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Here we can configure 3 parameters, include the Frequency, Preamble Index and

UL_Permbase. Then click the button to execute the planning.

5. Export the results

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Click the button to save the result as excel file.

6. Continue plan the neighbor

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Here we must import the site information which finished the frequency planning.

7. Cell radius calculate

Here we need configure the neighbor parameters which are marked with red circle.

8. Plan the neighbor

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Click the button auto plan the neighbor.

9. Export the neighbor plan

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When finish the neighbor plan, we can use the arrow button to check one

cell’s neighbor, use the button to export the neighbor result.

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