003 WCDMA Radio Network Coverage Planning ISSUE 1
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Transcript of 003 WCDMA Radio Network Coverage Planning ISSUE 1
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HUAWEI TECHNOLOGIES CO., LTD. All rights reserved
www.huawei.com
Internal
OWJ100101 WCDMA Radio Network Coverage
PlanningISSUE1.0
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Upon completion of this course, you will be able to:Know the contents and process of network planning.Understand the uplink budget and its elements.Understand the downlink budget and its elements.Familiarize the coverage enhancement technologies.
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Section 1 Process of WCDMA Network Planning Section 1 Process of WCDMA Network Planning
Section 2 Uplink BudgetSection 2 Uplink Budget
Section 3 Downlink Budget Section 3 Downlink Budget
Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies
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Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning
1.1 Overview of Radio Network Planning1.1 Overview of Radio Network Planning
1.2 Huawei Concept of Radio Network Planning 1.2 Huawei Concept of Radio Network Planning
1.3 Process of Radio Network Planning 1.3 Process of Radio Network Planning
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Definition and Category of Network Planning
Focus of the train: Planning of radio network.
Definition: Network planning means that proper network elements (NEs) are
selected according to the network target, network evolution requirement, and cost, and then the quality, configuration, and connection mode of the NEs are determined to facilitate engineering implementation.
Categories: Planning of core network Planning of radio network Planning of transmission network
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Importance of Radio Network Planning in 3G
Importance: The construction cost of the mobile
communications network mainly lies in the equipment investment.
Among the three parts of the 3G network (radio access network, transmission network, and core network), the radio access network occupies more than 70% investment.
The investment in the radio access network depends on the number and configuration of the BSs.
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Compare WCDMA Network Planning with that of GSM
In the GSM system, the structure and frequency of the cellular network are planned in order to ensure that the co-frequency and adjacent-frequency interference meet the call quality requirement.
If the interference requirement is met, the number of supported subscribers can be calculated based on the number of carrier frequencies and the number of timeslots.
The coverage of the GSM system depends on the transmit power of the transmitter and the demodulation performance of the receiver.
The GSM mainly offers voice service, and the GoS and design objective are relatively simple.
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WCDMA uses the spread spectrum technology, so it can realize 11 frequency multiplexing without frequency planning.
The capacity of each carrier in WCDMA is "soft" because it is related to factors such as environment and adjacent-cell interference.
The coverage of the WCDMA system is related to the system load. If the system load increases, the coverage will shrink.
The WCDMA system supports services with different rate and QoS, including voice service, and their coverage capacity is different. In the network planning, the system performance shall be optimized through reasonable planning and radio resource management.
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Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning
1.1 Overview of Radio Network Planning 1.1 Overview of Radio Network Planning
1.2 Huawei Concept of Radio Network Planning1.2 Huawei Concept of Radio Network Planning
1.3 Process of Radio Network Planning 1.3 Process of Radio Network Planning
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Huawei Concept of Wireless Network Planning Optimal coverage for profitable services
The 3G network is a multi-service network, so the network resources need be distributed among different services. The cell radius and coverage scheme should be determined after the profitable services and their coverage quality are determined. At the early stage of the 3G network, if the planning focuses on high-speed data service, it will result in waste of the BSs because there are not enough services.
Competitive core service Core service refers to the service that have a long-term effect on the network
development. It is possible that the core service is not profitable in a short period, but is the attraction of the subscriber increase and service development, for example, high-speed data service. Therefore, the quality of the core service should be guaranteed in order to show the service and performance advantages of the 3G network and promote the operator's brand.
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Huawei Concept of Wireless Network Planning
Highest capacity based on limited resources
The capacity of the 3G network is mainly affected by interference. Reasonable parameter planning may help to reduce intra-cell and inter-cell interference, improve the cell capacity, and make full use of the limited resources.
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Huawei Concept of Wireless Network Planning
Lowest overall cost of network construction
The construction of the radio network goes through the lifecycle of the network. In the planning, further development shall be considered, in order to reduce the total cost of network construction.
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Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning
1.1 Overview of Radio Network Planning 1.1 Overview of Radio Network Planning
1.2 Huawei Concept of Radio Network Planning 1.2 Huawei Concept of Radio Network Planning
1.3 Process of Radio Network Planning1.3 Process of Radio Network Planning
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Process of Wireless Network Planning
Radio Network Dimensioning (RND) At the early stage of the project planning, the future
network is preliminarily planned, and the configuration and the number of RAN NEs are output for preliminary project negotiation and for cost estimation in contract signing.
Pre-planning of radio network
At the mid stage of project planning, based on the dimensioning output, the future network is planned in detail, and the accurate network scale and theoretical site location are determined. A pre-planning report will be output for mid-stage project and cost estimation in contract signing.
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Process of Wireless Network Planning
Cell planning of radio network
At the later stage of project planning, based on the pre-planning output, each selected site is surveyed, and the related cell parameters are determined. If the result is quite different from the planning, the cell parameters and planning effect should be checked through simulation, and the output report would be the final radio network planning scheme that can guide the project implementation.
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Process of Radio Network Planning
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Radio Network Dimensioning
Radio network dimensioning is a simplified analysis of the future network. Objective:
To obtain the network scale (Approximate BS quantity and configuration), to obtain the construction period, and to obtain information such as electronical cost and human resource cost.
Method:Select a proper propagation model, and subscriber mobility, distribution, and traffic models, and then estimate the site quantity, cell quantity, coverage size and capacity.
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Requirement of RND parameters Information of coverage area
The engineers of RNP should know exact information about coverage area ,for example :
Area , economy, population Distribution of cluster The information of mobile communication market
Target of network The target of network should include several factors:
Service Coverage area & Coverage quality Network Capacity Target load of cell
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Requirement of RND parameters
Limited by network scale & Building plan in different phase
Base on commercial contract
Base on RND result if there is no commercial contract
Information of available site
For a new operator who doesnt have abundant 2G mobile communication network sites, the RNP engineer should collect exact information about available site.
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Radio Network dimensioning
Coverage information Coverage area Coverage probability
Capacity information Traffic model Service model Subscriber density
Quality information QoS requirement GoS requirement Demodulation threshold
System scale
Site quantity
System configuration
Sector structure
Carrier quantity
Network construction cost
Site cost
Equipment cost
InputInput OutputOutput
Coverage dimensioning
Capacity dimensioning
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Radio Network Pre-planning
Based on radio network dimensioning, the network pre-planning intends to determine the initial layout and theoretical location of the BSs and select engineering parameters (BS location, network hierarchy, transmit power, antenna layout/type/direction/tilt angle, and so on) and some cell parameters (common channel, transmit power of traffic channel, orthogonal factor, cell scrambling code, and so on) .
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Radio Network Pre-planning Based on the result of RND,
theoretical location of site, parameters of project, parameters of cell, We should carry out coverage simulation.
We should carry out more detailed adjustment (for example amount of NodeB, configuration of NodeB, antenna altitude, antenna azimuth) after analyzing the results of coverage simulation.
Finally ,we should get perfect coverage result.
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Radio Network Pre-planning Radio Network Pre-planning report
We should output Radio Network Pre-planning report after finishing previous jobs. Radio Network Pre-planning report should include following factors:
Introduce of project background Information of planning area :area, population, cluster Project of radio network pre-planning: site distribution map, site list
( include site name, latitude ,longitude, parameters) Performance of project :based on the simulation result Appendix: statistical diagram about performance
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Radio Network Cell Planning Flowchart of cell planning Flowchart of cell planning
N
Site survey report
Site selection
System emulation
Design objective
met?
Wireless network planning report
Noise test
Noise test report
Wireless network pre-planning
report
Site survey
N
NewSite
2G
Search
Rings
Yes
Site list
New site (prefix: NewSite)?
2G site?
Output Search Rings
Obtain candidate sites
Site conditions determined?
Site survey report
Site requirement
met?
Yes
Site survey
No
Noise test Noise test report
Wireless network pre-planning
report Yes
No
No
Yes
Yes
No
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Radio Network Cell Planning site survey In fact , perfect site position could not be acquired. We must select some backup
site. But how can we select the backup site? Based on experience , backup site is selected in SEARCH RING scope ,
SEARCH RING =1/4*R, at the same time ,we still consider its height. We still pay attention to some other factors when we select the backup sites :
Radio propagation Site position Site height Surrounding
Job implementation Space of room Antenna installation Transmission Power
Commercial factor Rent
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Radio Network Cell Planning System Simulation
System Simulation class
Static simulation Static simulation would gain the
performance of radio network based on snapshot
Dynamic simulation Dynamic simulation would gain the
performance of radio network based on analysis of mobile subscribers.
At present, Static simulation is in common use. Monte Carlo simulation is one type of static simulations
The example of Monte Carlo simulation
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The example about Monte Carlo simulation
100%100% 100%100%20%20% 60%60%
0%0% 75%75% 40%40%60%60%
Access ratioAccess ratio
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Distribution of NodeBs
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Simulation diagram pilot coverage intensity
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Simulation diagram pilot coverage quality (Ec/Io)
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Coverage probability of 12.2k voice service
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Coverage probability of 64k video phone service
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Coverage probability of 144k Net Meeting service
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Coverage probability of 384k HTTP service
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Simulation result about pilot pollution
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Summary of the Section
Categories of radio network planning
Huawei concept of radio network planning
Differences between GSM network planning and WCDMA network planning
Process of radio network planning
Input and output requirements of the radio network pre-planning
This Section covers the following: This Section covers the following:
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Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning
Section 2 Uplink BudgetSection 2 Uplink Budget
Section 3 Downlink Budget Section 3 Downlink Budget
Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies
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CapacityCoverageQuality Relation between capacity, coverage, and quality of the WCDMA
system The WCDMA system is a self-interference system, and its
capacity, coverage, and quality closely related to each other. Capacitycoverage (e.g. cell breath)
If the load increases, the capacity and interference also interference, and the coverage shrinks.
Capacityquality (e.g. outer loop power control) The system capacity may increase by lowering the quality of
some connections. Coveragequality (e.g. AMRC)
The coverage may increase by lowering the quality of some connections.
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Process of Coverage Budget Environment features of the
planned area
Site capacity
Indoor coverage
Coverage probability
Propagation model
Equipment performance
Create link budgetCreate link budget
Obtain cell radius Obtain cell radius
Calculate site area Calculate site area
Specify site quantity of the area
Specify site quantity of the area
Maximum path loss
Minimum cell radius
Maximum site coverage area
Site quantity=planned area/site coverage areaSite quantity=planned area/site coverage area
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Fundamental Principle
Link Budget: Link Budget intends to estimate the system coverage by analyzing the factors of the propagation of the forward signal and reverse signal, in order to obtain the maximum propagation loss after certain communications quality is ensured.
TX
CombinerDuplexer
Feeder
RX
Pout_BS
Lc_BSLf_BS
Ga_BSNodeB
TX
RX
Pout_UE
Ga_UEUE
CombinerDuplexer
PL_DLPL
_UL
Body Loss
FadingMargin
PenetrationLoss
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Algorithm Introduction
PL_UL=Pout_UE +Ga_BS+Ga_UE Lf_BS+Ga_SHO Mpc Mf MI Lp Lb S_BS
PL_UL: Maximum propagation loss of the Uplink Pout_UE: Maximum transmit power of the traffic channel of the UE Lf_BS: Cable loss Ga_BS: Antenna gain of the BS; Ga_UE: Antenna gain of the MS Ga_SHO: Gain of soft handover Mpc: Margin for fast power control Mf: Slow fading margin (related to the propagation environment) MI: Interference margin (related to the designed system capacity) Lp: Penetration loss of a building (used if indoor coverage is required) Lb: Body loss S_BS: Sensitivity of BS receiver (related to factors such as service and
multi-path condition)
Uplink (reverse)Uplink (reverse)
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Elements of WCDMA Uplink BudgetMax Power of TCHBody LossGain of UE Tx AntennaEIRPGain of BS Rx AntennaCable LossNoise Figure (BS)Required Eb/No (BS)Sensitivity of BS Receiver UL Cell LoadInterference MarginBackground Noise Level
SHO Gain over Fast FadingFast Fading MarginMinimum Signal Strength RequiredPenetration LossStd. dev. of Slow FadingEdge coverage ProbabilitySlow Fading MarginSHO Gain over Slow Fading
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Elements of WCDMA Uplink Budget 1.Max Power of TCH (dBm)
For a UE, the maximum power of each traffic channel is usually the nominal total transmit power. There are many types of UE in a commercial network, so this parameters should be reasonably set in the link budget according to the specifications of a mainstream commercial cell phone and the requirement of the operator.
Grade of UE power TS 25.101 v3.7.0 2001-066.2.1
+2/-2dB+21dBm4
+1/-3dB+24dBm3
+1/-3dB+27dBm2
+1/-3dB+33dBm1
ToleranceNominal maximum output powerPower Class
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Elements of WCDMA Uplink Budget
2. Body Loss (dB)For voice service, the body loss is 3 dB. Because the data service mainly involves reading and video,
so the UE is relatively far from body, and the body loss is 0 dB.
3. Gain of UE Tx Antenna (dBi) In general, assume that the receiver gain and transmitter
gain of the UE antenna are both 0 dBi. 4. EIRP(dBm)
UE EIRP (dBm) = UE Tx Power (dBm) - Body Loss (dB)+ Gain of UE Tx Antenna (dBi)
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Elements of WCDMA Uplink Budget 5. Gain of BS Rx Antenna (dBi)
Kathrein 741794
6.6kgWeight
1302 mm / 155 mm / 69 mm
dimensioning (Height / Width / Depth)
>30dBFront-to-back ratio, co-polar
>14dBSide lobe suppression for 1st side
lobe above horizon
Fixed, 2Electrical tilt
Horizontal: 63
Vertical:6.5HPBW (1920~2170MHz)
18.5dBiGain
+45, -45Polarization
1710~2170MHz (dual band for DCS and
UMTS)Frequency range
Kathrein 741790
5kgWeight
1387 mmdimensioning (Height)Fixed, 0Electrical tilt
Vertical: 7HPBW
11dBiGain
VerticalPolarization
1920~2170MHzFrequency range
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Elements of WCDMA Uplink Budget 6. Cable Loss (dB)
It includes the loss of the feeders and connectors between the cabinet top and the antenna connector.
Lower jumper Connector Feeder Upper jumper Etc.
Except for the feeder, the loss is relatively constant. Assume that the connecter loss is 0.8 dB.
7/8-inch feeder: 6.1 dB / 100m for 2GHz 5/4-inch feeder: 4.5 dB / 100m for 2GHz
Bracket
Bracket
Tilt adjuster
Antenna
Upper jumper
Feeder
Feeder windowLightning arrester
Lower jumper
Feeder fixing clip
Feeder grounding clip
Feeder installation
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Elements of WCDMA Uplink Budget 7. Noise Figure (dB)
Noise figure (NF): It is used to measure the noise performance of an amplifier. It refers to the ratio of the inputSNR to the output SNR of the antenna.
Thermal noise of receiver (unit bandwidth): PN = KTBWNF
= -174 (dBm/Hz) + 10lg(3.84MHz / 1Hz) + NF(dB)= -108 (dBm/3.84MHz) + NF (dB)
NF NF = = SNRSNRii / / SNRSNRoo= (S= (Sii / N/ Nii) / (S) / (Soo / N/ Noo))
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Elements of WCDMA Uplink Budget 8. Eb/No Required (dB)
It is obtained through link simulation. It is related to the following:
Configuration of receiver diversity
Multi-path channel condition
Bearer type
9. Sensitivity of BS Receiver (dBm)Sensitivity of Receiver (dBm)
= -174 (dBm/Hz) + NF (dB) + 10lg(3.84MHz/1Hz)+ required Eb/No (dB) - 10lg[3.84MHz/Rb(kHz)]
= -174 (dBm/Hz) + NF (dB) + 10lg[1000 * Rb (kHz)] + Eb/No (dB)
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Elements of WCDMA Uplink Budget
10. Background Noise Level (dBm)External electromagnetic interference sources:
Wireless transmitters (GSM, microwave, radar, television station, and so)
Automobile ignition
Lightning
For the planning for a specific area, it is recommended to estimate the local interference through noise test.
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Elements of WCDMA Uplink Budget 11. Penetration Loss (dB)
Indoor penetration loss refers to the difference between the average signal strength outside the building and the average signal strength of one layer of the building.
The penetration loss is related to building type, arrive angle of the radio wave, and so on. In the link budget, assume that the penetration loss is subject to the lognormal distribution. The penetration loss is indicated by average penetration loss and standard deviation.
It is uneconomical to provide better indoor coverage through an outdoor BS. The indoor coverage shall be provided through a reasonable indoor coverage solution.
In the actual construction of a commercial network, the penetration loss margin is usually specified by the operator in order to compare the planning results of different manufacturers.
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Elements of WCDMA Uplink Budget 12. Fast Fading Margin (dB)
In the link budget, the demodulation performance of the used receiver is the simulation result based on the assumed ideal power control. In an actual system, because of the limited transmit power of the transmitter, non-ideal factors are introduced in the closed loop power control.
Effect of power control margin on the uplink demodulation performance:
The simulation shows the following: When the HeadRoom is large, the target Eb/No set in the outer loop power control is appropriate to the simulation result under the ideal power control. As the power margin decreases, the Eb/No gradually increases (if the power margin decreases by 1 dB, the required Eb/No increases by about 1 dB). If power control performance is almost not available, the BER/BLER cannot be ensured.
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Elements of WCDMA Uplink Budget 13. Edge coverage Probability
When the transmit power of a UE hits the threshold, but the path loss does not meet the requirements for the lowest receive level, the link will be disconnected.
For a UE at a distance of d, the link disconnection probability is as follows:
(d) = Pmax_UE S_min 10lg(d)It refers to the difference between the average loss of the paths at a distance of d and the allowed maximum path loss for ensuring the connection.
The average fading component is 0, and the standard variation is
})(Pr{})lg(10_Pr{})lg(10_Pr{
})(_Pr{)(Pr_
minmax
minmax
minmax
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SF x ,( ) dnorm x 0, ,( ):=
30 20 10 0 10 20 300
0.02
0.04
0.06
SF x 8,( )SF x 10,( )SF x 12,( )
x
SF_M x ,( ) pnorm x 0, ,( ):=
20 16 12 8 4 0 4 8 12 16 200
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
SF_M x 8,( )SF_M x 10,( )SF_M x 12,( )
x
Elements of WCDMA Uplink Budget 14. Slow Fading Margin (dB)
Key point: Property of normal distribution.
Slow Fading Margin (dB) = required edge coverage ProbabilityStd. dev. of Slow Fading (dB)
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Elements of WCDMA Uplink Budget
15. Uplink Cell Load
Uplink cell load is used to measure the uplink load of a cell.
The higher the uplink cell load, the higher the uplink interference.
If the uplink load is about 100% , the uplink interference becomes infinite, and the corresponding capacity is the limit capacity.
( ) ( ) ( ) +=+= N jjjN jUL WvREbvsNo
iLi11
11
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Elements of WCDMA Uplink Budget
16. Uplink Interference Margin (dB)UL
N
jN
TOT
LPINoiseRise
=
==
1
1
1
1
1
50% Load 50% Load 3dB3dB60% 60% LoadLoad 4dB4dB75% 75% LoadLoad 6dB6dB
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Elements of WCDMA Uplink Budget
17. SHO Gain over Fast Fading (dB)The soft handover gain includes two parts:
Multiple related soft handover branches lower the required margin for fading, which results in multi-cell gain.
Gain for the link demodulation of the soft handover macro diversity combining gain.
The SHO Gain over Fast Fading refer to the macro diversity combination gain.
This value is obtained through simulation. The typical value is 1.5 dB.
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Elements of WCDMA Uplink Budget
18.SHO Gain over Slow Fading (dB)As mentioned above, the soft handover gain
includes two parts: Multiple irrelevant soft handover branches lower
the required margin for fading, which results in multi-cell gain.
Gain for the link demodulation of the soft handover marco diversity combination gain.
The SHO Gain over Fast Fading refers to the macro diversity combining gain.
This value is obtained through simulation.
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Elements of WCDMA Uplink Budget
19. Minimum Signal Strength Required (dBm)After the interference factors and the factors
degrading the performance are considered, the signal strength required by the correct demodulation is receiver sensitivity in the network.
Minimum Signal Strength Required= Sensitivity of Receiver (dBm) - Gain of Antenna (dBi)+ Body Loss (dB) + Interference Margin (dB)+ Margin for Background Noise (dB) - SHO Gain over fast fading (dB) + Fast Fading Margin (dB)
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Elements of WCDMA Uplink Budget
Summary: Cell edge path loss Based on the maximum path loss allowed by the link,
the path loss at the cell edge can be calculated if the fading margin and soft handover gain for providing the required edge/area coverage probability and the penetration loss of indoor coverage are considered.
Path Loss (dB) = [ EiRP (dBm) - Minimum Signal Strength Required (dBm) ]- Penetration Loss (dB) -Slow Fading Margin (dB) + SHO Gain over Slow Fading (dB)
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Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning
Section 2 Uplink BudgetSection 2 Uplink Budget
Section 3 Downlink BudgetSection 3 Downlink Budget
Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies
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Fundamental Principle
Link Budget: Link Budget intends to estimate the system coverage by analyzing the factors of the propagation of the forward signal and reverse signal, in order to obtain the maximum propagation loss after certain communications quality is ensured.
TX
CombinerDuplexer
Feeder
RX
Pout_BS
Lc_BSLf_BS
Ga_BSNodeB
TX
RX
Pout_UE
Ga_UEUE
CombinerDuplexer
PL_DLPL
_UL
Body Loss
FadingMargin
PenetrationLoss
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Algorithm PL_DL=Pout_BS Lf_BS+Ga_BS+Ga_UE +Ga_SHO Mpc Mf MI Lp
Lb S_UE PL_DL: Maximum propagation loss of the downlink Pout_UE: Maximum transmit power of the traffic channel of the BS Lf_BS: Cable loss Ga_BS: Antenna gain of the BS; Ga_UE: Antenna gain of the MS Ga_SHO: Gain of soft handover Mpc: Margin for fast power control Mf: Slow fading margin (related to the propagation environment) MI: Interference margin (related to the designed system capacity) Lp: Penetration loss of a building (used if indoor coverage is required) Lb: Body loss S_UE: Sensitivity of UE receiver (related to factors such as service and
multi-path condition)
Downlink (forward)Downlink (forward)
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Elements of WCDMA Downlink Budget Max Power of TCHCable LossGain of BS Tx AntennaEIRPGain of UE Rx AntennaBody LossNoise Figure (UE)Required Eb/No (UE)Sensitivity of UE Receiver DL Cell LoadingInterference MarginBackground Noise Level
SHO Gain over Fast Fading
Fast Fading Margin
Minimum Signal Strength Required
Penetration Loss
Std. dev. of Slow Fading
Edge coverage Probability
Slow Fading Margin
SHO Gain over Slow Fading
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Elements of WCDMA Downlink Budget 1.Downlink Cell Load
Downlink cell load factor is defined in two ways: Downlink cell load at the receiver:
This definition is similar to that of the uplink cell load: The higher the downlink cell load, the higher the cell transmit power,
and the higher the receiver interference. When the downlink cell load is 100% , the corresponding capacity is
the limit capacity of the downlink. Downlink cell load at the receiver: The ratio of the current cell transmit
power to the maximum BS transmit power. Characteristics: The higher the downlink cell load, the higher the cell transmit power.
The downlink cell load is related to service type, UE receiver performance, cell size, and BS capability.
( ) ( )
+=
N
jj
jjjDL vWR
EbvsNoi1
1
Currently, the later definition is used in the link budget tool.Currently, the later definition is used in the link budget tool.
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: 1.78
Elements of WCDMA Downlink Budget 2.Downlink Interference Margin (dB)
Downlink interference at UE receiver:
The downlink load factor is:
The link budget tool uses the following typical values:
orthogonal factor : It is obtained through simulation. It is related to environment type and cell radius.
Cell edge adjacent-cell interference factor
N
N
N
nnj
T
j
Tj
N
total
P
PPL
PPL
P
PIjNoiseRise
++
==
=1
,
1)1()(
jDLf , =
N
n nj
ownj
PLPL
1 ,
,
j
( ) ( )=
+=
J
jjDLj
jjjobDL fW
RVNE1
,)1(/ ,where = ,where =
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Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning
Section 2 Uplink BudgetSection 2 Uplink Budget
Section 3 Downlink Budget Section 3 Downlink Budget
Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies
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Tower Mounted Amplifier (TMA)
TMA
A TMA locate the position under the antenna
A TMA is Low noise amplifierA TMA helps to improve the
uplink receive sensitivity and enhances the uplink coverage
A TMA usually has 0.7dB loss in the downlink.
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Academic calculation about TMAAcademic calculation about TMA improve the uplink receive sensitAcademic calculation about TMA improve the uplink receive sensitivityivity
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The example of academic calculation about TMA improve the uplink receive sensitivity
Receiver Chain Noise FigureWithout TMA: 2.433+2.2 dBWith TMA 1.57 dB
The example of academic calculation about TMA
2.2NodeB
-2.4332.4337/8"Cable30m + 0.6dB Connector Loss
121.45TMA
GainNoise FigureEquipment
Gain 3.063dB for uplink when using TMAGain 3.063dB for uplink when using TMA
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4-antennas Reception Diversity
4Antenna reception diversity 4Antenna reception diversity has
two typesTwo Cross-polarization
antennasFour antennas
4Antenna reception diversity helps to improve the uplink reception performance
Improve the uplink coverage and capacity performance
4Antenna reception diversity need equipment support
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4-antennas Reception Diversity
4RxDiv principle diversity gain
Resist fast fadingCorrelation combinationGain relates to multi-
path ,service ,speed, antenna performance
2RxDiv> 4RxDivReduce the requirement of
Eb/No
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4-antennas Reception Diversity
Compared with a double-antenna reception diversity, 4-antenna reception diversity requires lower Eb/No.
Gain of 4-antenna reception diversity (compared with double-antenna reception diversity)
1.391.772.5RA120Rural area
RA120
TU3
TU3
Channel
1.77
1.73
1.73
Capacity-based gain
1.39
1.37
1.37
Coverage-based gain
2.5Suburb
2.4Common urban
area
2.4High-density urban area
Eb/No improvement Area
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