Wcdma Rnp Cw Test Guidance-20040719-A-1.1

8/13/2019 Wcdma Rnp Cw Test Guidance-20040719-A-1.1

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Product name Confidentiality level

WCDMA RNP For internal use only

Product version

V100R001Total 21 pages

WCDMA RNP Continuous Wave Test Guidance

(For internal use only)

Prepared by URNP-SANA Date 2002/07/29

Reviewed by Date

Reviewed by Date

Reviewed by Date

Huawei Technology Co., Ltd.

All rights reserved


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WCDMA RNP Continuous Wave Test GuidanceFor internal use only

Revision Record

DateRevision

version

Description Author

2002/07/29 1.00 Initial transmittal Liu Yu &Liu Yong

2002/09/09 1.01 Revision completed based on reviewcomments

Liu Yu

2002/09/09 1.10 The drive test distance table is added,and the guide to the drive testequipment operation is revised.

Liu Yu

2005-07-03 All rights reserved Page 2 of 19


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Table of Contents

1 Principle and Purpose of CW Test..........................................................................................................8

1.1 Electromagnetic Wave Propagation Model in Mobile Communication .................................8

1.1.1 Influencing Factors of the Electromagnetic Wave Propagation......................................8

1.1.2 Classification of the Electromagnetic Wave Propagation Model ...................................8

1.2 Characteristics of Radio Signal Propagation...........................................................................9

1.3 Purpose of CW Test ..............................................................................................................10

1.4 Basic Principles of CW Test .................................................................................................10

2 CW Test Flow.......................................................................................................................................11

2.1 Site Selection ........................................................................................................................11

2.1.1 Site Selection Principle .................................................................................................11

2.1.2 Site Selection Criterion .................................................................................................12

2.2 Test Environment..................................................................................................................12

2.3 Drive Test .............................................................................................................................14

2.3.1 Drive Test Flow ............................................................................................................14

2.3.2 Test Route .....................................................................................................................14

2.3.3 Drive Test Speed...........................................................................................................15

2.3.4 Bad Data in Drive Test..................................................................................................15

2.4 Special Condition Treatment ................................................................................................152.4.1 Ec Test ..........................................................................................................................15

2.4.2 Directional Antenna......................................................................................................16

3 Test Result Analysis .............................................................................................................................16

4 Appendix 1: Guideline for CW Test Tool Operation.........................................................................16

4.1 Hardware Connection ...........................................................................................................16

4.2 Software Setting....................................................................................................................17

4.2.1 Database File Creation..................................................................................................17

4.2.2 Project Creation ............................................................................................................17

4.2.3 Parameter Configuration...............................................................................................17

4.2.4 Data Collection .............................................................................................................18

4.2.5 Data Export ...................................................................................................................18

5 Appendix 2 CW Test Parameter Table .................................................................................................20



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List of Tables

table 1 CW test distances in different environments ................................................................................15

table 2 CW test parameter table................................................................................................................20



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List of Figures

figure 1 Schematic diagram of site selection criterion .......................................................................12

figure 2 CW test environment ............................................................................................................13

figure 3 Drive test equipment connection diagram.............................................................................16

figure 4 Operation Graphic Illustration 1 ...........................................................................................17

figure 5 Figure 1 Operation Graphic Illustration 2.............................................................................18

figure 6 Figure 1 Operation graphic Illustration 3.........................................................................19

figure 7 Operation graphic Illustration 4 ............................................................................................20



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WCDMA RNP Continuous Wave Test Guidance

Key words: WCDMA CW test (Continuous wave test) Drive test equipment

Abstract: This document introduces the collection methods and flow of the electromagneticwave propagation data in the target area for the CW test, so as to obtain the accurate

electromagnetic wave propagation model for the network planning before the WCDMA

network setup; it also describes the principles that must be followed to guarantee the

accuracy of the test data.



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1 Principle and Purpose of CW Test

To obtain the radio propagation model compliant with the actual environment of the local area, to

improve the accuracy of the coverage prediction, and to make good preparation for the network planning,the propagation model tuning is necessary. CW test is the continuous wave test, which is the important step

in the model tuning. The data for the model tuning can be obtained through the CW test and the digital

map. The latitude and longitude information and the receiving level in these data constitute the data

source for the model tuning.

1.1 Electromagnetic Wave Propagation Model in Mobile Communication

1.1.1 Influencing Factors of the Electromagnetic Wave Propagation

The propagation model is the base of the cell planning in mobile communication network. The

accuracy of the propagation model is related to the rationality of the cell planning, and it is also related to

that whether the operators meet the subscriber's requirements with relatively economical investment.

Because of the wide land in our country, the propagation environments in different provinces and cities are

various. For instance, compared with that of the city in the plain area, the propagation environments of the

city in the hilly area are distinctively different, and their propagation models are different from each other.

Therefore, if considering only the experiences but without considering the influences by different

parameters, such as the different terrain, clutter , constructions and the plant covers, the coverage and the

quality problems will occur in the established network, or the established NodeBs are in too high density,

resulting in resource waste. With the rapid development of the mobile communication network in our

country, the operators pay more and more attentions to the matching problems between the propagation

models and the local environments. The propagation environment plays the key role in the radio

propagation model setup. The main factors that determine the propagation environment of a specific area

include:

1. Natural terrains (mountains, hills, plains, water areas, etc.);

2. Number, heights, distributions and material properties of the man-made

constructions;

3. Plant cover characteristics in the area;

4. Weather;

Furthermore, the radio propagation model is also influenced by the system working frequency and the

mobile station movement. In the same areas, if the working frequencies are different, the receiving signal

fading conditions will be different; the propagation environment of the static mobile station is distinctively

different from that of the fast moving mobile station.

1.1.2 Classification of the Electromagnetic Wave Propagation Model

The study on the propagation model can be divided into two types: one is the theoretical analysis

method based on the radio propagation theory; the other is the actually testing statistics method based on



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quantities of test data and experience formulae.

In the mobile communication system, because the mobile station moves continuously, the propagation

channel is influenced not only by the Doppler effect, but also by the terrines and the clutters. In addition,

the own interference of the mobile system and the outside interference cannot be neglected. Based on the

above-mentioned properties of the mobile communication system, it is difficult to realize strict theoretical

analysis, it is usually required to approximate and simplify the propagation environment, which will lead

to big error of the theoretical model. The most famous statistics model is the Okumura model, which is the

propagation model expressed in the curve diagram made through the statistics based on quantities of the

test data by Okumura in Japan. On the basis of the Okumura model, use the regression method to simulate

the analytic experience formula for the computer calculation. Those experience formulae include the

Okumura-Hata formula applied to GSM900 macro cell and the Hata extension formula applied to

GSM1800 macro cell. In addition, there are also the Walfisch formula applied to the micro cell and the

Keenan-Motley formula applied to the indoor propagation environment. The calculations of these

experience formulae are complicated and with big or small errors with the actual environment. Therefore,

in the actual field strength prediction, the corrected Okumura-Hata model is usually taken as the prediction

model,. In the planning software, the propagation model can be tunned after CW test according to the

actual local radio environment.

1.2 Characteristics of Radio Signal Propagation

The radio signal will be influenced in propagation by the multipath fading, which can be expressed as:

P(d)=Pt*d-nS(d)R(d) (1)

Where, P(d) refers to the received signal power, which is the function of the distance between the

NodeB and the mobile station; d-n

refers to the space propagation loss, and n is usually 3 ~ 4; S(d) refers to

the shadow fading, which is caused by the rolling terrain, the constructions and other obstacles in the

propagation environment, and it is also called long-term fading or slow fading; R(d) refers to the multipath

fading, which is caused by the multipath propagation of the mobile propagation environment, and it is also

called short-term fading or fast fading.

The property of slow fading agrees with the logarithm normal distribution, while fast fading agrees

with the Rayleigh distribution or the Ricean distribution. Fast fading is the fast jitter overlapping on

slow fading. Because the antenna height of the common mobile station is lower than the height of the

surrounding constructions, and the carrier wavelength is far smaller than the construction size, the dynamic

changing range of the signal in the distance of half a wavelength can reach 40dB (higher than the mean

value by 10dB, and lower than the mean value by 30dB) at the sides of the mobile station.

For the mobile communication system, the analysis in Formula (1) is not very convenient; in order to

carry out the analysis on the mobile communication propagation by means of the random process theory,

Formula (1) can be expressed as:

r(x) = m(x)r0(x) (2)



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Where, x refers to the distance, r(x) refers to the received signal; r0(x) refers to the Rayleigh fading;

m(x) refers to the mean value, which is the composition of long-term fading and space propagation loss,

and it can be expressed as:

3

Where, 2L refers to the mean length of the sampling interval, and it is also called the intrinsic length.

Because the terrain and the clutter are fixed in a certain period, for a specified site, the mean value

at a specified location is definite.

+

=

Lx

LxdyyrLxm )(2

1)(

1.3 Purpose of CW Test

As described above, the electromagnetic wave propagation model is closely related to the specific

terrain and clutter. There is usually big error in the classic propagation theoretical analysis, so the actual

test statistics method is adopted in practice, that is, correct the experience formula with quantities of test

data; in this case, CW test is necessary. m(x) in Formula (3) is the mean value, which is the data expected

to be measured and recorded in CW test. It is the value most approximate to the predicted value of the

propagation model. This document describes only the collection method and flow of the test data

required for the model tuning, but not to discuss the tuning method of the experienced propagation model

with the actually tested data.

Note that, if the model parameters of the cities with the similar terrain and clutter are available, they

can be used directly in the coverage prediction. In this case, it is unnecessary to repeat CW tests and model

tuning, so as to save the human and the material resources.

1.4 Basic Principles of CW Test

Since the basic purpose of the CW test is to correct the electromagnetic wave propagation model of an

area by using the electromagnetic wave propagation test data of the typical area, and to apply this model to

the target area. Therefore, CW test should follow at least the two basic principles below:

1. Typicalness. The collected test data must be typical enough to represent the

electromagnetic wave propagation property in this area. For example, there are

mountains and plains in an area, so the data collection should cover these two conditions.

Another example, in a test, if the satellite is blocked in GPS location, or there are high

constructions blocking at the near end of the transmission antenna, the bad data will

probably occur, and they must be filtered in the post-processing; otherwise they will

influence seriously the typicalness of the test data. The influencing factors of the

electromagnetic wave propagation properties in a certain area are extensive, including

terrain, clutter, etc., these factors should be considered in CW test.

2. Balance. The collected test data must reflect the electromagnetic wave propagation

properties of an area "in proportion". For example, in a certain area, the mountain area



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takes 20% of the total area, and the plain area takes 80%, the test data should reflect this

proportion approximately for the purpose of weighting in important areas. In data

collection, besides the balance between terrain and clutter, the balance between distance,

height and direction should also be considered. For instance, in a CW test, if most test

data are collected within a range beyond 1000m away from the site, but few data are

collected within it, when the propagation model is tunned with the test data, the far end

(beyond 1000m) of the propagation model curve will be accurate, while the near end of

the curve is inaccurate . From this example, we can know that the balance of CW test is

closely related to the test purpose.

Some points of attention will be introduced in Part 2-CW Test Flow in this document, and they are

presented based on the basic principles, and the main purpose is to guarantee the accuracy and the

typicalness of the test data.

2 CW Test Flow

There are 3 steps in the CW test: site selection, setup the test platform and drive test.

2.1 Site Selection

2.1.1 Site Selection Principle

In order to carry out the CW test, it is necessary to select an appropriate site to transmit RF signal.

Firstly, the CW test serves the planning of the business network , so its site selection should follow the

principle of the site selection of the business network, for instance, the antenna height selection. Secondly,

the following special principles for site selection should be followed in CW test:

1) The site number. Before test, it is necessary to identify the test site location and the

number of sites. According to the general experiences, in the big city with dense

population, the test sites should be no less than 5; for the medium or small city, one

site is enough. This mainly depends on the antenna height of the test site and its

EIRP .

2) Typicalness. The site selection principle is to make the station cover all types of

clutters in the planning area (The clutter types come from digital map.).

3) Multiple types of models. If multiple models are required to describe the

propagation properties of the test environment, the area corresponding to each

model should be well defined (e.g., different geographical conditions, distance by

which the antenna is higher than the clutter, etc.). Only in this case, the model of

each area can be clearly marked; meanwhile, the transition area between the

models should be as small as possible.

4) Areas overlapping. Increase the measurement overlapping areas to the maximum;however, ensure that the distance between the sites is appropriate.



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5) Obstacles. If there are distinctive obstacles, they should be filtered in the data

post-processing. Furthermore, because of the limit of the installation conditions, the

temporary omni-directional antenna will probably be installed at the building sides,

thus the signals in the other siides direction will probably be blocked by the building,

and the building itself becomes the obstacle. In this case, attention should be paid

to the test route for the path selection. Ensure that the test route is in the direction

where the signals have not been blocked and avoid to go into the shadow area.

2.1.2 Site Selection Criterion

In the actual tests, site selection can be carried out in convenience for the tests according to the

following criterion:

The antenna height should be more than 20m;

The antenna should be higher than the nearest obstacle by more than 5m.

5m

figure 1 Schematic diagram of site selection criterion

The obstacle herein refers mainly to the highest building on the roof where the antenna is. As the site,

the building should be higher than the average height of the surrounding buildings.

2.2 Test Environment

After the site is selected, start to setup the test platform.

An individual tone RF signal is required for CW test. Transmit RF signal with the amplifier and the

antenna, and receive it with the drive test equipment. The transmission subsystems include transmission

antenna, two pieces of feeders, high power amplifier, high-frequency signal source and antenna support.

The receiving subsystems include test receiver, GPS receiver, test software and portable computer.



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figure 2 CW test environment

After the setup of the test platform is finished, open the signal source to transmit RF signal, and start

the drive test. In CW test data post-processing, the effective isotropic radiated power (EIRP) of the test site

should be known, so it is necessary to record the signal gain by each part of the CW test environment

diagram:

1) transmission power of the signal source;

2) loss of RF cable 1;

3) gain of the amplifier;

4) loss of RF cable 2;

5) gain of the transmission antenna;

6) gain of the receiving antenna.

Meanwhile, in the practice of the project, pay attention to the following :

1) The signal source. Adjust the transmission power to make the transmission power at the antenna

interface be between 5W and 20W (Since it is the individual tone signal transmited, the receiving

sensitivity is high, which is usually 5W.). Before the test on the system, the initial transmission power of

the low signal source should be set to avoid the radiation damage.

2) The sum of the lengths of RF cable 1 and RF cable 2 should be bigger than 10m at least, so as toensure that the RF signal has little radiation on human body.

3) In the amplifier selection, pay attention to its gain, so as to ensure enough power transmited by

antenna, such as, bigger than 5W.

4) The omni-directional antenna is usually adopted as the transmission antenna.

5) The receiving antenna gain is usually 0dBi.

6) The antenna height is bigger than 20m, and higher than the roof by more than 5m, as described in

2.1.

7) If there is no pole resource for the antenna post on the roof, the antenna support should be prepared

in advance.



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2.3 Drive Test1

2.3.1 Drive Test Flow

1. Test route selection

Before test, determine the test route on the map. The test route should agree with the principles as

described below.

2. Drive test

2.3.2 Test Route

In the test route selection, divide the areas with the similar terrains and clutters according to different

geographical forms at first, or divide the areas according to the digital map information, and then design

the route according to:

1)Terrain:The test path must cover all the main terrains in the area.

2)Height:If the terrain in the area rolls up and down abruptly, the test path must cover the terrains

with different heights.

3)Distance: The test path must cover the positions in the area at different distances to the site.

Because the calibration distance of CW test is mainly in the influencing range of the site, it is

unnecessary for the test distance to exceed 2 times of the future cell radius. Forthe drive test distance

in the typical environment, refer to Table1.

4) Direction: The test numbers of the points in the longitudinal and in the latitudinal directions

should be consistent with each other, because when the mobile station is within 3km away from the test

site, the received signal will be influenced seriously by the site surrounding building structures and the

antenna height; the signal strength parallel to the signal propagation direction differs from that vertical to

the propagation direction by about 10dB.

5) Length. The total route length of a CW test should be bigger than 60km.2Note that the test

length herein refers to the route length after geographical averaging, and the repeated route can only be

calculated once. After the route is designed, the route length can be read from the digital map.

6) Point Number.The more the test points, the better. Generally, it is better that the number of

the test points of each site should be more than 10000, or the test time should be over 4 hours.

7) Overlapping. The test paths of different sites can be overlapped to the maximum, so as to improve

the tunned model reliability.

8) Obstacle.When the antenna signal is blocked by the building at a side of the antenna, the vehicle

route should be arranged appropriately. Do not go into the shadow area behind the building at this side.

1There are three sampling methods with the professional CW test equipment: sampling according to time;

sampling according to pulse; sampling according to distance. Only the test equipment with which the

sampling is made according to time is discussed in this document.

2According to the sampling rate of 1 point/6m after sampling data smoothing, 10000 points should be sampled in the testroute no less than 60km.



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table 1 CW test distances in different environments

Environment Dense urban Urban Suburb RuralVoice coverage radius (km)(without indoor coverage)

1.78 2.16 5.87 23.62

Corresponding drive test

distance (km)

4.2 5 14 56

Voice coverage radius (km)(with indoor coverage)

0.48 0.81 2.97 16.8

Corresponding drive testdistance (km)

1.2 2 5 40

Note: The coverage radius in the above table are obtained according to the link budget tool in

Reference [3] (take the smaller one of the uplink and the downlink coverage radius as the cell coverage

radius), the uplink and downlink loads are both set to 50%, and the drive test distance is obtained by

multiplying the coverage radius by 2.4 (multiply the coverage radius by 2, and then add with 20% margin).

2.3.3 Drive Test Speed

The drive test speed is related to the two factors below:

1) Sampling distance d: the distance between adjacent sampling points should be around ~/4; in

this case, the influence by Rayleigh fading can be thoroughly eliminated.

2) Sampling frequency f: which refers to the sampling points of the drive test equipment within 1s.

The upperlimit of vehicle speed is determined by the following conditions:

The moving distance of the drive test vehicle during the time that the drive test equipment takes to

obtain 1 sampling point equals to the sampling distance d(the distance between the sampling points),

namely:

(1/f )*v=d

So,v=f*d, where, dis within~/4.

Suppose that the drive test equipment supports the sampling frequency of 1000HZ, have d equal to

the carrier wavelength (0.15m) at 2G band, the upper limit of the vehicle speed will be 150m/s, namely

540km/h. If dis equal to /4, the upper limit of the vehicle speed will be 135km/h.

2.3.4 Bad Data in Drive Test

The bad data (test results in abnormal conditions) must be removed from the sampling data, for

example, the test results in the following conditions::

The fading exceeding 15~30db that can not be explained (e.g. the fading caused

by obstacles within 200m away from the site);

In the tunnel;

Under the viaduct.

2.4 Special Condition Treatment

2.4.1 Ec Test



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If NodeB is available for an area to be tested, the CW test can be carried out by measuring Ec value.

In this case, note:

1. The receiver sensitivity is low, which limits the test range.

2. The receiver sampling frequency is low, which limits the maximum vehicle speed.

2.4.2 Directional Antenna

The discussion above is based on the condition that the omni-directional antenna is adopted in CW

test. If the directional antenna is used for CW test, note:

1.The test route should be selected from the main lobe coverage area of the antenna.

3 Test Result Analysis

The data file of the CW test result is the database file of "*. mdb". The text file can be exported

through Agilent drive test software, and then it will become a "*.dat" file after certain format

post-processing; finally, it can be imported into ASSET for model tuning.

4 Appendix 1: Guideline for CW Test Tool Operation

The drive test equipment of Agilent E7476A is adopted for the receiving subsystem of CW test

to collect data; this equipment provides a dedicated module for CW test. The operation steps of CW test

are described below:

4.1 Hardware Connection

E7476A is a signal receiver with embedded in GPS, but it requires a portable computer to install its

control software. In the test, plug a hardware security key in the portable computer. The entire equipment

connection diagram is as follows:

figure 3 Drive test equipment connection diagram



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4.2 Software Setting

4.2.1 Database File Creation

Run the control software "Agilent E74xx Series" in the portable computer, select the menu "file

>new database", and create a "*.mdb" file in the selected directory.

4.2.2 Project Creation

Create a "project" under the database file: Click the button "new", and input "project" name. Then the

hardware of this "project" should be configured: Click the buttion "hardware", two items will appear:

"Computer Monitor" and "PC Clock"; and two additional items are required, which can be configured

automatically: Click the button "Auto Config" >next>cancel "Create new pject">Finish. If the auto

configuration succeeds, two items will be added: E6455C (IMT2000 Receiver) and GPS (Internal TSIP); if

these two items have not been added, it means that the auto configuration failed. Check whether the

hardware and the hardware security key are connected.

figure 4 Operation Graphic Illustration 1

4.2.3 Parameter Configuration

Consequently, carry out the parameter configuration on this "project". Click the button "collection",

when the five icons below turn green, it means normal. Click the second icon, a interface appears, as

shown in the following figure: Select "CW Power List" in the red circle, and select "1.25MHz" in the blue

circle; adujst RBW to the minimum value of 8.36kHz where there is a green circle, and add the frequency

(e.g. 2140MHz) where there is a yellow circle. After these parameters are set, click the "save" buttion to

save these parameters configurations under "project", and then start the measurement. In addition, it is also

allowed to open the map window and the spectrum window for aid observation.



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figure 5 Figure 1 Operation Graphic Illustration 2

4.2.4 Data Collection

Click the fourth button (Record key) of the 8 buttons in the left column in the interface to start the

data record. The recorded "dataset" can use the default name, or change the name manually. Attention

should be paid to that, when a configuration parameter changes, the measurement cannot be started until

the change of the parameter has been saved in "Project", In case the data record needs to be paused

because the vehicle has to stop before red traffic light or goes into the tunnel, click the third button (pause

key) of the 8 buttons in the left column to break off the data record. When the record is required again,

click the first button to resume to record. Thus the data will be recorded into a dataset. The data record can

also broken off by clicking "Record" key (the fourth button), and click it again to resume; in this case,

the data will be saved in different dataset (Datasets can be exported to be one text file at last.).

4.2.5 Data Export

After the data are collected, they are saved in "*.mdb" file, so they are required to export to be the text

file format. The export method is as follows: Open the saved "*.mdb" file, click the button "Export", and

an export interface will appear. On the right is a button column, click Add Plan>input "Plan" name

(Next)>click "Add" icon (Note: do not select "Alarms" and "Notes" below)>select "CW Power List"



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where "Result" is; others are optional (as shown in Figure1 below) >Next >Next >Select

"Mapinfo-compatible file" where "Output" is, and select WGS84 where "Datum" is (refer to Figure 2

below)>Next>Finish. The newly-added "Plan" will appear in "Export Plans" column on the left; select

this "Plan", and click "Export" on the right>Select Project (Next)>Select "Dataset" to be exported

(Next)>Next>Input the exported file name>Finish; thus the data will be automatically exported into

the file. And the exported file can be used for model tuning.

figure 6 Figure 1 Operation graphic Illustration 3



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figure 7 Operation graphic Illustration 4

5 Appendix 2 CW Test Parameter Table

Before the drive test is started, the following table should be completed:

table 2 CW test parameter table

Site name

Site longitude

Site latitude

Site height

Antenna type (omni/dir.)

Signal source transmit power (dBm)

RF Cable 1 length/loss (dB)

RF Cable 2 length/loss (dB)Amplifier gain (dB)

Transmit antenna gain (dBi)

Receiving antenna gain ((dBi)



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WCDMA RNP Continuous Wave Test Guide For internal use only

List of references:

[1] Huawei Network Planning Department, Cell Planning Theory, Document Room of

Shangshai Research Center,2001

[2] Yang Puqu 2GHz Frequency Segment Spread Module Revision Analysis Report

_Ver2.0_ 0605.doc Document Room of Shangshai Research Center,2002[3] Wang Mingmin, Miao Jiashu etc,WCDMA Uplink and Downlink Budget

Table,Document Room of Shangshai Research Center,2002

Wcdma Rnp Cw Test Guidance-20040719-A-1.1

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