Nokia UltraSite WCDMA BTS Optima Compact (WREB), BTS Description
Og 102 site survey and layout of bts issue1.5
-
Upload
ketut-widya -
Category
Technology
-
view
186 -
download
2
description
Transcript of Og 102 site survey and layout of bts issue1.5
HUAWEI TECHNOLOGIES CO., LTD.
www.huawei.com
HUAWEI Confidential
Security Level:
Site Survey and Layout of BTS
ISSUE 1.5
Wireless Case & Training Department
HUAWEI TECHNOLOGIES CO., LTD. Page 2HUAWEI Confidential
Foreword
The survey and layout of BTS is the basis of construction for radio mobile network. It has the following functions:
Showing the system design of the network planning Determining the structure of future network Determining the quality of network operation
Thus, the proper survey and layout of BTS can ensure the installation, maintenance, and network planning.
HUAWEI TECHNOLOGIES CO., LTD. Page 3HUAWEI Confidential
Purpose
•Service flow of BTS survey
•Selection of site address
•Design of antenna
After learning this course, you should be
familiar with:
HUAWEI TECHNOLOGIES CO., LTD. Page 4HUAWEI Confidential
Contents
Chapter 1 Service Description
Chapter 2 Preparation
Chapter 3 Site Selection
Chapter 4 Antenna Design
Chapter 5 Survey Document
HUAWEI TECHNOLOGIES CO., LTD. Page 5HUAWEI Confidential
Service Description
Survey task
Optical test
− Surrounding architecture environment and
nature environment
Spectrum measurement
− Electromagnetic environment
Site check
− Installation condition of antenna and
equipment
− Power supply and transmission supply
Survey purpose
Collect the site information required by the networking planning and
environment description. Check whether the site meets the requirements of
construction.
HUAWEI TECHNOLOGIES CO., LTD. Page 6HUAWEI Confidential
Service Description
According to width of band, determine frequency multiplex mode
According to capacity forecast, traffic distribution, and coverage
requirement, estimate the required quantity of BTSs.
Confirm the position of BTS in theory.
Perform BTS survey
Design parameters of cell
Network hierarchy structure, transmit power, antenna system,
including the type, height, direction, and down tilt of antenna
Position of BTS survey in the network planning
HUAWEI TECHNOLOGIES CO., LTD. Page 7HUAWEI Confidential
Radio network estimation report
Site information
Whether there is a site
Obtaining spare sites
Site survey Whether
conforming site condition
Survey report
Whether meeting requirements of
site
Obtaining site; selecting radius
Electromagnetic environment test
Yes
No
Yes
NoYes
No
Service Flow
HUAWEI TECHNOLOGIES CO., LTD. Page 8HUAWEI Confidential
Contents
Chapter 1 Service Description
Chapter 2 Preparation
Chapter 3 Site Selection
Chapter 4 Antenna Design
Chapter 5 Survey Document
HUAWEI TECHNOLOGIES CO., LTD. Page 9HUAWEI Confidential
Be familiar with the engineering and collect the materials that is
related to the project :
Engineering document
Background material
Network status
Map
Configuration list
Preparation
HUAWEI TECHNOLOGIES CO., LTD. Page 10HUAWEI Confidential
Prepare the following tools that are
available:
Digital camera
GPS satellite receiver
Compass
Ruler
Laptop
Preparation
HUAWEI TECHNOLOGIES CO., LTD. Page 11HUAWEI Confidential
Preparation
Survey preparation coordination meeting
Before survey, call in all the relative personnel to hold the survey preparation
coordination meeting. The main contents of this meeting are listed as follows:
Testing electromagnetic background
Arranging survey and coordination personnel
Preparing vehicle and equipment
Making survey plan and confirming survey route
Offering the primary schemes of transmission
and power
HUAWEI TECHNOLOGIES CO., LTD. Page 12HUAWEI Confidential
Contents
Chapter 1 Service Description
Chapter 2 Preparation
Chapter 3 Site Selection
Chapter 4 Antenna Design
Chapter 5 Survey Document
HUAWEI TECHNOLOGIES CO., LTD. Page 13HUAWEI Confidential
Site Selection
After completing preparation and knowing about the coverage requirements, start to
select site.
When confirming the site, consider the following information:
Original network condition
Population distribution and local custom
City structure and town distribution
Main streets and traffic flow
Mountainous region, lake, river, and coastline
Long-term development trend
HUAWEI TECHNOLOGIES CO., LTD. Page 14HUAWEI Confidential
Principles of Selecting Site
Choosing sites in the
heavy-traffic region and
concentrated subscriber
region
Population distribution
Traffic distribution
Subscriber flow direction
Principle Principle
Surrounding environment
Signal propagation quality
Trying not to choose sites near
mountain, radar, broadcasting
station, forest, and electrical
factory
HUAWEI TECHNOLOGIES CO., LTD. Page 15HUAWEI Confidential
The specific principles are described as follows:
Construct BTS on the ideal position of a cell. The offset sho
uld not exceed the ¼ of coverage radius.
Under the condition of the BTS layout is not affected, choo
se the existing equipment to reduce the construction cost a
nd period as possible .
To control the coverage range, reduce the difficulty of engin
eering construction, and be convenient for maintenance, do
not choose the sites on the mountain that is on the border o
f the city or suburb.
(the relative altitude to the city: beyond 100m ~ 300m)
Principles of Selecting Site
HUAWEI TECHNOLOGIES CO., LTD. Page 16HUAWEI Confidential
Principles of Selecting Sites
Construct the BTS at a place where transport is fluent, supply of
mains is available, environment is safe, and there is a few filed.
Do not construct the BTS near the high-power radio transmit
station, radar station, and other interference sources.
Construct BTS at a place that is far away from the forest to avoid
the fast fading of received signal.
Consider the signal reflection and time dispersion when
constructing the sites in the mountainous area, precipitous shore,
dense lake area, highland city, and the environment with high
metal building.
When choosing site in the complex, realize the division of network
structure according to the height of building.
At the early stage of constructing network, because of a few of
BTSs, ensure good coverage in important areas.
HUAWEI TECHNOLOGIES CO., LTD. Page 17HUAWEI Confidential
Contents
Chapter 1 Service Description
Chapter 2 Preparation
Chapter 3 Site Selection
Chapter 4 Antenna Design
Chapter 5 Survey Document
HUAWEI TECHNOLOGIES CO., LTD. Page 18HUAWEI Confidential
Selecting Antenna Selecting Antenna
Selecting Antenna
The selection for antenna is an important part of determining the network
quality.
According to the requirements of coverage and service quality, traffic
distribution, landform, coverage in the entire network, and interference, to
select the antenna.
According to landform or traffic distribution, the environment of using
antenna can be categorized into:
City, suburb, countryside, highway, mountainous area, offing, tunnel,
and indoor environment
HUAWEI TECHNOLOGIES CO., LTD. Page 19HUAWEI Confidential
Principles of Selecting Antenna
Selecting Antenna for the BTS in the city
Choose the directional antenna with 60° ~ 65° half power angle.
Choose the antenna with about 15dBi gain.
Choose the antenna with 3° ~ 6°tilt angle.
Choose dual polarization antenna.
HUAWEI TECHNOLOGIES CO., LTD. Page 20HUAWEI Confidential
Principles of Selecting Antenna
Selecting antenna for the BTS in the suburb
According to actual conditions, choose the directional antenna with
65°or 90° half power angle.
Choose 15 ~ 18dBi middling or high gain antenna.
According to actual conditions, determine whether the tilt angle sho
uld be used.
Dual polarization antenna and vertical polarization antenna are bot
h available.
HUAWEI TECHNOLOGIES CO., LTD. Page 21HUAWEI Confidential
Principles of Selecting Antenna
Selecting antenna for the BTS in the countryside
According to actual conditions, choose 90°or 120° directional ant
enna or omni-directional antenna.
Choose directional antenna with 16 ~ 18dBi gain.
Do not choose presetting tilt antenna. Choose null filling antenna
for the high BTS.
The vertical polarization antenna is recommended.
HUAWEI TECHNOLOGIES CO., LTD. Page 22HUAWEI Confidential
Principles of Selecting Antenna
Selecting antenna for the BTS on the
highway
In general, choose narrow-beam and high-gain directional antenna. According to actual conditions, you also can choose 8-shaped antenna or omni-directional antenna.
Because the BTS on the highway must cover a long distance, do not choose the presetting tilt antenna.
The vertical polarization antenna is recommended.
The front-to-back ratio of the directional antenna should not too great.
HUAWEI TECHNOLOGIES CO., LTD. Page 23HUAWEI Confidential
Principles of Selecting AntennaPrinciples of Selecting Antenna
Selecting antenna for the BTS in the tunnel
Tunnel shorter than 2 km
Install the 10dB-12dB Yagi antenna/log-periodic
antenna/flat antenna in the jaws of tunnel to cover
a road that is less than 2km.
Tunnel longer than 2 km
Use leaky feeder, coaxial cable, and fiber
distribution system.
HUAWEI TECHNOLOGIES CO., LTD. Page 24HUAWEI Confidential
Principles of Selecting AntennaPrinciples of Selecting Antenna
Selecting Indoor Antenna
Omni-directional antenna
Vertical polarization, 2dBi gain, cap-shaped or cup-shaped, small
size, convenient for installation, graceful
Directional antenna
Vertical polarization, 90°half power angle
7dBi gain
HUAWEI TECHNOLOGIES CO., LTD. Page 25HUAWEI Confidential
Antenna Height
Due to the installation space or cell planning, the heights of antenn
as that are in different cells of a BTS can be different.
For the BTS in the city, the height of antenna is about 25m.
For the BTS in the suburb, the height of antenna is about 40m.
If an antenna, particularly the omni-directional antenna, is too high,
the coverage level of the place that nears to the antenna may be lo
wered, that is, no signal under the power.
In addition, the too high antenna may lead to cross coverage and i
ntra-frequency/neighboring-frequency interferences that affect the
network quality.
Principles of Design for Antenna Height Principles of Design for Antenna Height
HUAWEI TECHNOLOGIES CO., LTD. Page 26HUAWEI Confidential
Principles of Design for Antenna Azimuth Angle Principles of Design for Antenna Azimuth Angle
Azimuth Angle
Based on signal coverage, ensure that the azimuth angles of three sectors are the
same. Adjust the azimuth angles of antennas according to important coverage obje
cts on the border of city and suburb, in the traffic artery and isolated site of suburb.
To enhance the signal strength and improve call quality, adjust the major lobe of an
tenna to face to the heavy-traffic areas.
To control interference, adjust the major lobe of antenna to be apart from intra-freq
uency cells.
The cross coverage areas of neighboring cells in the city should not exceed 10%.
The cross coverage areas of neighboring cells in the suburb and village should be
not too large. The azimuth angle of neighboring cells should not less than 90°.
To avoid cross coverage, do not make the major lobe of antenna face to the
straight streets in the crowded areas.
HUAWEI TECHNOLOGIES CO., LTD. Page 27HUAWEI Confidential
Principles of Design for Tilt Angle Principles of Design for Tilt Angle
Tilt Angle
The beam tilt is a basic technology for improving Frequency Reuse capa
bility.
The antenna tilt technology is used to control coverage scope and reduc
e the interferences in the system.
To reduce the interferences from co-channel cells and meet the coverag
e requirements, set the tilt angles based on specific conditions.
The design for tilt angle should be based on transmitter power, antenna
height, cell coverage, and radio environment.
HUAWEI TECHNOLOGIES CO., LTD. Page 28HUAWEI Confidential
Tilt Angle The antenna tilt is categorized into electrical mode and mechanical mode. T
he angle of the electrical tilt is relative to the model of antenna. The angle of
the mechanical tilt is adjustable, but it is limited by installation accessory an
d signal transportation. Often the angle should not exceed 15°.
The electrical tilt and mechanical tilt have surface radiations that differ with t
he increases of angles.
HUAWEI TECHNOLOGIES CO., LTD. Page 29HUAWEI Confidential
Installing Antenna A. Installation Environment
The installation environment contains the ambient of antenna
and that of BTS.
For the ambient of antenna, check the isolation between
antennas and impacts of tower and roof on antennas.
For the ambient of BTS, check whether the high buildings that
are 500m away have impacts on signal transportation.
HUAWEI TECHNOLOGIES CO., LTD. Page 30HUAWEI Confidential
2〉 10
12~ 10
0.50~ 2GSM1800M
3.5〉 30
310~ 30
21~ 10
0.50~ 1
GSM900M
h( m)D( m)FREQ
Installing Antenna
When installing antenna, consider whether the ambient affects the
coverage cell. Keep the antenna away from barriers. If you need to
install antenna on the roof, try to install it on the edge.
HUAWEI TECHNOLOGIES CO., LTD. Page 31HUAWEI Confidential
Installing Antenna
B. Antenna Isolation
The receiver and transmitter must have a certain isolation.
Isolation between antennas: Attenuation of signal from a anten
na port to another
GSM system: The isolation between two transmitter antennas
and the isolation between the transmitter antenna and the rec
eiver antenna should be not fewer than 30dB.
− Antenna vertical layout: Lv=28+40log(k/λ)(dB)
− Antenna horizontal layout: Lv=22+20log(d/λ)-(G1+G2)-(S1
+S2)(dB)
HUAWEI TECHNOLOGIES CO., LTD. Page 32HUAWEI Confidential
C. Requirements for Space of Diversity
When you perform space diversity, the distance between two receiver antennas
should be 12λ to 18λ.
When an antenna is installed highly, the horizontal space of the diversity
antenna should be large. Usually the space of diversity antenna is 0.11 times of
the height of the antenna.
To achieve the same effort, the vertical diversity space should be five to six
times of the horizontal diversity space.
To reduce the mutual effects of two antennas, the horizontal diversity space
should be more than 3m.
Installing Antenna
HUAWEI TECHNOLOGIES CO., LTD. Page 33HUAWEI Confidential
Contents
Chapter 1 Service Description
Chapter 2 Preparation
Chapter 3 Site Selection
Chapter 4 Antenna Design
Chapter 5 Survey Document
HUAWEI TECHNOLOGIES CO., LTD. Page 34HUAWEI Confidential
Survey report Survey report
Survey Document
The standard survey report provides service for the subsequent network planning and network optimization. It is the guarantee of engineering quality and the basis of planning for network capacity.
The survey report consists of survey table and memo.
The survey table records the longitude and latitude of a BTS, antenna design, and ambient.
Shoot the picture of BTS coverage area in the direction of north. Get eight pictures every 45°.
HUAWEI TECHNOLOGIES CO., LTD. Page 35HUAWEI Confidential
Illustration of Survey Document
Survey Table
Engineering Parameter Table
HUAWEI TECHNOLOGIES CO., LTD. Page 36HUAWEI Confidential
Surrounding of BTS
Installation platform
Thank You www.huawei.com