Rf network design

1
Procedure of CDMA
RF Engineering
(RF Network Design)
2001. 5.
Jongwoo@netsgo.com

2
1. Network Design Objective……………….…..3P
2. RF Network Design Procedure……...……..5P
Stage 1: Preparations …...………………………...6P
Stage 2: Wireless Environment Analysis …….21P
Stage 3: Coverage Design ………………………36P
Stage 4: Parameter Design ……………………..50P
Stage 5: Dimensioning …………………………..59P
Contents

Acceptable Coverage
Forward & Reverse Link Quality
Capacity
 To Resolve
 To Manage
 To Ensure
Engineering Requirement vs.
Available Equipment
Customer Complaints
Pilot Pollution
Cell Overlap / Handoff Regions
1. Network Design Objectives

Design Value
Design Criteria
? %
FER
(Frame Error Rate)
? %
GOS
(Blocking Rate)
? %
Coverage
Probability
- Demand for Service Coverage?
- Demand for Service Quality?
- Demand Service Capacity?
- Usable Frequency Bandwidth?
- Service Criteria?
- Call Completion Rate?
- Handoff Success Rate?
Design Objectives
1. Network Design Objectives

5
2. Network Design Procedure
Basic Data Collection &
analysis
Design Criteria Setup
GIS Data Conversion
Preparations
Competition Coverage Measurement
Plan Setup
Region Clustering
Site Survey Plan
Site Acquisition
Site Coverage Simulation
Link Budget Analysis
Base Station Design On the
Map Positioning
Site survey & Field
measurement
Measurement data integration
Path loss calculation
RF Environment Analysis
Outdoor/Underground
Coverage design
In-building and underground
Coverage Design
Pilot Assignment
Paging Capacity & Paging
zone
Handoff neighbor list, etc.
Parameter Design
Required BTS
Required FA
Required CHC / CE
Dimension & Report
STAGE 1
STAGE 2
STAGE 3
STAGE 4
STAGE 5

6
Target Objective Setup Competitor’s Info. Analysis Sheet Detail Design Criteria
- Service Target Area(In Building/In car) - Traffic & Coverage data
- FER(Frame Error Rate) - Coverage hole(If possible)
- GOS(Grade Of Service)
- Coverage reliability
General Statistic Data for
Design Scope
- Population and Area
- Traffic and BTS info./ GIS MAP
- Telecommunication regulation
Competitor’s Service Information
- Service Area and Quality
(GSM,CDMA)
- BTS Info.(Lon/Lat, Traffic & antenna)
Design Objective
- GOS/FER/Coverage Reliability
- FA capacity
- Cell coverage criteria
- Soft Handoff region ratio, etc.
General Statistics Data gathering & Analysis
- RF Engineering Scope Analysis
(Area, Population, Building Density, etc)
- Traffic Information(Traffic Distribution analysis)
(Traffic volume, call success/completion rate)
- BTS Information(Lon/Lat, coverage, etc)
Competition company Traffic Volume
and Quality Analysis(If Possible)
- BTS and antenna type, position
- Traffic analysis per each cell/sector
- Overall BTS coverage analysis
Detail Design
Criteria Setup
Required Data/Tool
Main Activity
Accomplishment
Stage 1: Preparations
Overview

7
Setup the Design Criteria
GOS vs. Capacity
0
10
20
30
40
50
60
70
80
90
0.0% 0.1% 0.5% 1.0% 1.5% 2.0% 2.5% 3.0% 3.5% 4.0% 4.5% 5.0% 5.5% 6.0% 6.5% 7.0% 7.5% 8.0% 8.5% 9.0% 9.5% 10.0%
GOS
Erlang
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
CapacityIncreaseRatio
Erlang Capacity Increase Ratio
Traffic Model : Soft Blocking Model
BTS Type : 3 Sector
Channel : 84
Maximum User : 33
Sector Load Ratio : 1.5
GOS(Grade of Service), Blocking Probability

1
1.5
2
2.5
3
3.5
4
1 2 3 4 5 6 7 8 9 10 11 12 13
% FER
MeanOpinionScore
MOS
• PSTN = MOS 4
• CDMA = 3.6 (FER 1%)
MOS Vs. FER Graph (8K Vocoder)

 Coverage Area and Contour Reliability(FADE MARGIN)
95% Area Reliability 95% Contour Reliability
15% Contour failure
< 10%
< 5%
< 1%
Percent Failure 4-6% Contour failure
< 3%
< 2%
< 1%
Percent Failure
85% contour reliability 97% area reliability

10
0.5
0.6
0.7
0.8
0.9
1
1.1
σ/n
FractionofTotalAreawithSignalabove
Threshold.Fu
0 1 2 3 4 5 6 7 8
PX0
(R) = 0.95
0.9
0.85
0.8
0.75
0.7
0.65
0.6
0.55
0.5
Area Reliability Fu
Contour Reliability
σ = Standard deviation[dB]
n = Path slope
Path Loss varies as 1/rn
,
PX0
(R) = Coverage Probability on area boundary (r = R)

11
0
5
10
15
20
25
0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95
Location Probability at Cell Edge
FadeMarginindB
12 dB
11
10
9
8
7
6
Standard
Deviation
Fade Margin -----> 10 dB

 Coverage Area and Contour Reliability(FADE MARGIN)
Item Dense Urban Urban Suburban Rural
Slow Fading 10 dB 8 dB 8 dB 6 dB
Slow Fading
It follows the log-normal distribution with standard deviation
It depends on a variety of morphology
To obtain the exact slow fading value,
must perform the field measurement which consumes the high cost and time

13
FA Capacity(based on IS-95A reverse link)
• Limited by Interference From Other users
• Based on minimum required [Eb/It]minimum
• Relationship between [Eb/It]minimum and Number of user N
based on Perfect Power Control, No Thermal Noise, and
Isolated Single Cell
RSN
RS
It
Eb
/)1(
/
−
= 1
/
/ +=
ItEb
RWN
• S: Received signal at the base station(from power controlled mobiles)
• R: Data rate
• W: CDMA Bandwidth(1.2288 Mbps)
• Eb: Bit energy, It: Spectral Density of the total interference
• N: Number of active users

14
Pole(Maximum) Capacity(based on IS-95A reverse link)
No
W
IoIocvSN
RS
It
Eb
N
N
+
+−
=
)/1()1(
/
)1()1(1 fvN
W
R
It
Eb
W
R
It
Eb
NoW
SN
+−−
=
• Including the effects of Thermal Noise, Voice Activity and other
cell interference
Io
Ioc
f ≡,where

15
Pole(Maximum) Capacity(based on IS-95A reverse link)
• Pole(Max) Capacity, where required
• Obviously, this capacity can never be exceed in any cell/station
• Pole(Max) Capacity/Sector
1*1*
min)(
max += F
v
It
Eb
R
W
N
1)
3
55.2
(*1*
min)(
secmax/ += F
v
It
Eb
R
W
torN
f
F
+
=
1
1,where

16
FA Capacity(based on cdma2000
1x)
)%80%100
max
,()(_
00
=×= ∑∑ ==
S
k k
k
S
k
k
N
N
WhenMbitsMbitsCapacityFA
• Because of difference in required Signal /Noise, Activity and
Transmission velocity in each service
Nmaxk can be defined follows
)
/6.0
1
where,()1
/
(max
IoIoc
FSG
NtEb
FPG
N
kk
k
k
+
=⋅+
⋅
⋅
=
α
• Base station FA capacity of service carrying number of S with
various transmission velocity

17
Cell Coverage
• Coverage Criteria in CDMA System
- Forward Coverage : Design by the standard of Pilot CH Ec/Io
- Reverse Coverage : Design by the standard of Traffic CH Eb/No
• As higher Ec/Io and Eb/No criteria are arranged, better call
quality can be supplied for customers but more cost is also
expected. Therefore, criteria should be arranged to meet the
customer satisfaction and cost efficiency
Required Ec/Io
Required Eb/No
Forward Coverage
Reverse Coverage
>= -14dB
>= 6dB

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Soft Handoff Region Ratio
Soft Handoff Region Ratio
0
10
20
30
40
50
60
70
80
-22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11
T_ADD (dB)
RegionRatio(%)
2Way Soft Handoff 3Way Soft Handoff Total Soft Handoff
• T_ADD is used to add new Active/Candidate set
• T_DROP is used to reduce the Active pilot
• Because the output power of a mobile station decreases in handoff,
the interference also decreases and the BTS capacity increases.
But required channel resource also increases.
• 30 ~ 40 %

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 PILOT_INC parameter setting
 PN offset reuse distance calculation
 PN offset allocation
- PILOT_INC selection
- Distance between the same PN cell sites
- Extra PN offsets for expansion of cell sites or Micro cells
PN Increment and Allocation
Paging channel Load and Paging zone design
 Paging channel load calculation
 Paging zone design(1st
, 2nd
Paging zone)

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Х
Х
Х
Tx/Rx-0 Tx/Rx-1
10λ=3.6m
10λ=3.6m0.3m(MIN)
Competitor - ANT.
Х
Х
Х
0.3m(MIN)
Competitor-ANT.
Space Diversity Polarization Diversity
Single
Site
Joint
Site
Tx/Rx-0
Tx/Rx-1
Tx/Rx-0 Tx/Rx-1
Tx/Rx-0 Tx/Rx-1
• Distance between Antennas

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Region
Clustering
Maximum Cell Radius,
Minimum Antenna
Height Calculation
Site Survey and
Field Measurement
Competitor’s Coverage
Analysis
Link Budget
Analysis
Procedure Overview
Stage 2: RF Environment Analysis

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1. Site Survey Report
2. Field Measurement Data and Analysis Result
- Measurement Integration & Propagation Modeling
3. Frequency Planning
4. Competitor’s Coverage Analysis Result
MAP DATA
- Digital Map for CellPLAN
- 1:10,000 Traffic Map
Cell Planning Tool
Field Measurement Tool
- Transmitter / Receiver
- Spectrum Analyzer, etc
Measurement Tool
- AMPS/CDMA or GSM System
Competitor’s Cell Info.etc.
Region clustering
- Dense Urban, Urban, Suburban, Rural.
- Drive Survey for region clustering
Site Survey & Field Measurement
- Make the Site Survey list
- Drive Route establishment
- Perform the Field Measurement
Spectrum Clearance Check
(including Site Survey List)
Frequency Planning Review or Setup
- FA Planning
Measurement Tool
- AMPS/CDMA or GSM System
Required Data/Tool
Main Activity
Accomplishment

23
 Region Clustering by the Geographical Configuration
(Flat, Hilly, Mountain)
 General Clustering by the Map Data
(Rural, Suburban, Dense, Urban)
 Extraction of the Regional Parameter Values such as BAI(Building
Area Index), BSD(Building Size Distribution), BHD(Building Height
Distribution), VI(Vegetation Index) etc., using the Geometry Function
 Applying the Extracted Parameters to the Target Area to Achieve
more Detail Region Clustering
 Precisely Divided Region Clustering
Region Clustering

24
Region Clustering(Quantitative)
Region Class BAI(%)
BSD(m2
) BHD(Floors)
VI(%)
Avg. STD Avg. STD
Rural Flat, Hilly, Mountain < 12 - - - - -
Suburban
Residential(Open) 12 ~ 20 95 ~ 115 55 ~ 70 2 1 >= 2.5
Residential
(no Open)
20 ~ 30 100 ~ 120 70 ~ 90 2 ~ 3 1 <= 5
High-rise residential > = 12 >= 500 >= 90 >= 4 1 <= 2
Urban
Shopping Area 45 ~ 50 200 ~ 250 >= 180 >= 4 1 0
Commercial Area 30 ~ 40 150 ~ 200 >= 160 3 1 0
Industrial Area 35 ~ 45 >= 250 >= 200 2 ~ 3 1 <= 1
Dense
Urban
Shopping Area >= 50 200 ~ 250 >= 180 >= 4 1 0
Commercial Area >= 40 150 ~ 200 >= 160 6 1 0
Industrial Area >= 45 >= 250 >= 200 7 ~ 8 1 <= 1
[Reference] David Parsons “ The mobile radio propagation channel”

25
Site Survey and Field Measurement Procedure
Planning
1. Selection of target Building
for site survey
2. Scheduling for site survey
and field measurement
3. Planning for Drive route
Site Survey & F.M**
1. Check the test equipment
and visit site(building)
2. Take a a photograph and
fill
out the site survey report
3. Install the transmitter on
the roof of the building
4. Install the receiver in a car
5. Put the transmitter on
6. Start the driving test
7. Perform the Site survey &
field measurement result
analysis
- Path loss analysis
8. Perform the Competitor’s
coverage measurement
Test Equip.* Verification
1. Check the spectrum
analyzer self-generated
noise level & accuracy
2. Setup the Transmitter and
check the output power
level
3. check the Amplifier Gain by
using signal generator and
spectrum analyzer
4. Measurement of Cable loss
- between transmitter and AMP
- between AMP and Antenna
* Equip.: Equipment
** F.M: Field Measurement

26
Site Survey Planning
 Candidate sites shall be selected in each morphology to represent
the characteristics of that region and then team organization and
scheduling for the site survey and the field measurement shall be
made. And the drive route should be decided based on the main road
and the road condition
 make a plan for site surveying & field measuremnt
 select a variety of candidate site
 organize the team for site surveying
 decide the drive route

27
Site Survey Report
4
Date :
Site ID :
Visitor :
Bldg . Address :
Bldg . Height : Steel Tower Height : m
Latitude : Longitude :
Special Comment :
Department store,
Government office,
Competitor site,
Hotel, University,
Above the10th-story bldg .
Picture No :
Avg . Bldg . Height :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:
Picture No :
Major Bldg .:

28
Field Measurement
- Test Equipment Verification
Checking of the spectrum analyzer
Self-generated Noise level & accuracy
Setting up the Transmitter and
Checking Tx Output Power level
by using Spectrum Analyzer
Checking the LPA Gain by using Signal
Generator and Spectrum Analyzer
Measurement of Cable Loss
a. Between Transmitter and AMP
b. Between AMP. and Antenna

29
Field Measurement
- Drive Test: All road test as possible as can go
FA “A”
(Central Channel# A)
FA “B”
(Central Channel# B)
Team A
Team B
MS_1 MS_2
MS_3 MS_4
10Km
10Km
Site A
Site B
Measurement Radius

30
Field Measurement
- Measurement Data Analysis(1)
 Perform the Data Gathering and Analysis
 Calculate the distance for each measurement point
 Calculate the average Rx level for unit area (30m * 30m)
 Calculate the average Rx level for distance
 Path Loss Calculation
 Path Loss = Transmit signal Power – Received signal power [dBm]
Path Loss data is used to perform the Measurement integration to
calculate the exact Propagation model
By using the Cell Planning tool,
It will be easy to perform the MI

31
Field Measurement
- Measurement Data Analysis(2)
Propagation
Prediction Model
Measurement Data
Signal Strength
Distance
Propagation
Prediction Model
Measurement Data
δ
Signal Strength
Distance
-δ
MEASUREMENT INTEGRATION(MI)

32
Competitor’s Coverage Measurement / Analysis
 Collecting Information about the Specification of the
Competitor’s System
• The site location
• The height of the building and the tower
• Antenna type
• The direction and the angle of the antenna
• Control channel number and the output power by each sector
 Measuring the Service Quality
• GPS data(altitude & logitude)
• Cell ID (best sever / neighbor cell)
• Rx power (best sever / neighbor cell)
• BCCH (best sever / neighbor cell)

33
Link Budget Analysis
OBJECTIVES OF LBA
 To estimate the Maximum Allowable Path Loss for the
Reverse Link
 To estimate Maximum Allowable Path Loss for the Pilot, Sync, and
Paging Channels, including the appropriate path imbalance
 To compute the required percentages of Base Station transmit
power for the Pilot, Sync, Paging and Traffic Channel
 To estimate cell coverage and count

34
Link Budget Analysis(Reverse Link)
Reverse Link
MAPL
LBA
Operating Parameters:
System % Loading, SHO gain
Subscriber Parameters:
Maximum Power
Cable loss
Antenna Gain
Noise Figure
Noise Figure
BS Parameters:
Antenna Gain
Losses
Voice Activity & Reuse Factor
Technology Parameters:
Bandwidth, Data Rate ( Proc. Gain)
Required Eb/It
Propagation Parameters:
Fade Margin, Penetration Loss

35
Link Budget Table(Example: SKTelecom)
Uni t Val ue Remar k
Fr equency MHz 877 Cust omer
Bandwi dt h MHz 1. 2288 Spec.
Dat a Rat e bps 9600 Cust omer
Pr ocessi ng Gai n dB 21 Cal cul at ed
%Loadi ng % 50%Cust omer
Requi r ed Ar ea Rel i abi l i t y % 95%Cust omer
Mor hpol ogy Cl ass D. Ur ban Ur ban S. Ur ban Rur al Open Remar k
At Mobi l e St at i on ( TX)
Mobi l e Tx Power dBm 23. 0 23. 0 23. 0 23. 0 23. 0 Spec. ( Cl assI I I )
Ant enna Gai n dBi 0. 0 0. 0 0. 0 0. 0 0. 0 Cust omer
Body Loss dB 3. 0 3. 0 3. 0 3. 0 3. 0 Cust omer
At Base St at i on ( RX)
Noi se Densi t y( KT) dBm/ Hz - 174. 0 - 174. 0 - 174. 0 - 174. 0 - 174. 0 Spec.
Noi se Fi gur e( F) dB 5. 0 5. 0 5. 0 5. 0 5. 0 Vendor Spec.
Noi se Bandwi dt h dB 60. 9 60. 9 60. 9 60. 9 60. 9 Spec.
Noi se( KTBF) dBm - 108. 1 - 108. 1 - 108. 1 - 108. 1 - 108. 1 Cal cul at ed
Requi r ed Eb/ Nt dB 6. 0 6. 0 6. 0 6. 0 7. 0 Vendor Spec. f or 1%FER
Loadi ng Cor r ect i on ( 1- x) dB 0. 0 0. 0 0. 0 0. 0 0. 0
Sensi t i vi t y dBm - 123. 2 - 123. 2 - 123. 2 - 123. 2 - 122. 2 Cal cul at ed
Recei ve Ant enna Gai n dBi 18. 0 18. 0 14. 1 14. 1 14. 1 Cust omer
Cabl e & Di pl exer Loss dB 3. 0 3. 0 3. 0 3. 0 3. 0 Cust omer
SHO Gai n dB 3. 0 3. 0 3. 0 3. 0 3. 0 Cust omer
At Radi o Channel
Sl ow Fadi ng dB 10. 0 8. 0 8. 0 6. 0 3. 0 Cust omer
At t en. Fact or of Pr opagat i on dB/ dec 3. 5 3. 5 3. 5 3. 5 3. 5 Cal cul at ed
S. F/ A. F 2. 9 2. 3 2. 3 1. 7 0. 9 Cal cul at ed
Fade Mar gi n dB 11. 0 8. 5 8. 5 6. 0 3. 5 Cal cul at ed
At Ser vi ce Condi t i on
Requi r ed Cont our Rel i abi l i t y % 87. 0 86. 0 86. 0 83. 0 75. 0 Cal cul at ed
Penet r at i on Loss ( i n car ) dB 5. 0 5. 0 5. 0 5. 0 5. 0 Cust omer
Penet r at i on Loss ( i n bui l di ng) dB 18. 0 15. 0 10. 0 10. 0 10. 0 Cust omer
Out put
Max. Al l ow. PL ( on st r eet ) dB 150. 2 152. 7 148. 8 151. 3 152. 8 Cal cul at ed
Max. Al l ow. PL ( i n car ) dB 145. 2 147. 7 143. 8 146. 3 147. 8 Cal cul at ed
Max. Al l ow. PL ( i n bui l di ng) dB 132. 2 137. 7 138. 8 141. 3 142. 8 Cal cul at ed
MS Ant enna Hei ght 1. 5 1. 5 1. 5 1. 5 1. 5
BS Ant enna Hegi ht 21. 0 25. 0 30. 0 45. 0 45. 0
Max. Al l ow. Di st ance( on st r eet ) km 6. 2 8. 0 6. 9 10. 2 11. 3 Cal cul at ed
Max. Al l ow. Di st ance( i n car ) km 4. 5 5. 8 4. 9 7. 3 8. 1 Cal cul at ed
Max. Al l ow. Di st ance( i n bui l di ng) km 1. 97 3. 0 3. 6 5. 2 5. 8 Cal cul at ed

36
• Outputs
- Sites location
- Antenna type
- Antenna tower height
- Antenna orientation / tilt
- O/H Output power
- Candidate site location
- Site acquisition report
- Coverage Plot
- Recommendation on
next candidate sites
• Considering Factors
- Maximum cell radius
- Traffic distribution
- Competitor’s coverage
Designing on
the Map
Finding-out
Sites Location and
Initial Parameter Value
Site Acquisition
Coverage
Simulation
Coverage Design Procedure
Stage 3: Coverage Design Ⅰ

37
Design on the Map result CellPLAN simulation Plot Equp. Type Decision(Initial)
- Anchor site position result - Initial coverage design map - Initial Capacity analysis
- Cell site Position(Morphology) FWD Ec/Io, REV Eb/Nt Plot - Traffic estimation per cell site
H/O region analysis plot
Mobile ERP Plot
MAP DATA
CellPLAN Tool
- SKTelecom Design Tool
- Initial coverage simulation)
Map Info S/W
- Design on the Map(Note PC based)
LBA Result
- Maximum cell radius
- Minimum antenna height
- Minimum cell site no
Design on the Map with MAP INFO Tool
- Anchor site selection
(In Dense Urban area, high traffic density)
- Site positioning through the anchor site
CellPLAN Coverage Simulation
- Initial Coverage design by using
CellPLAN Tool(FWD/REV Coverage)
- Initial Capacity analysis based on
the traffic prediction
Equip. Type Decision(Initial)
- BTS, Small BTS, pico BTS
- Fiber optic Micro cell
- RF Repeater
Required Data/Tool
Main Activity
Accomplishment

38
Design on the MAP
 Coverage design consists of designing on the map, site acquisition
and coverage simulation. Especially, site acquisition and coverage
simulation is verified and modified repeatedly to achieve optimal
coverage design(Iterative)
 Cell site location is decided on the map by means of using the
maximum cell radius, competitor’s site location and the result of the
coverage analysis with consideration of estimated traffic in future
Initial Coverage Simulation
 After designing on the map, it must qualify the cell site location
through the coverage simulation by using RF planning Tool(In case
of SKTelecom, there is a cell planning tool named CellPLAN)
- Forward / Reverse Coverage simulation
- Soft handoff region, etc

39
Existing Network Traffic Analysis Procedure
PEG Data Collection
and Validity Check
Site/Sector’s Representative
Carried Traffic and
Blocking Rate Calculation
• PEG count data collection for 2 Weeks
• Abnormal data deletion (Beyond the limit of Avg Traffic ± 50%)
- Too small traffic by an obstacle of BTS
- Excessive traffic by PEG counting errors
• Representative Carried Traffic
= Avg Carried Traffic + 1.28 * Std
(Range of 90% reliability)
• Blocking rate calculating for each sector and site
• Offered Traffic = Carried Traffic
* (1+Blocking Rate)Site/Sector’s Offered
Traffic Calculation
Traffic Distribution Analysis

40
• Divide total area into unit area(Aij)
• Decide weighting factor each unit
area (Wij)
• Σ Wij = 1
Traffic Distribution
1
2
3
j
n
1 2 3 i m
Wij
W11 W12 W13
W21 W22 W23
W32 W33W31
Wnm
Traffic Weighting Map(Mobile Telecom Introduction Stage)
- Traffic Volume
- Population Density
- Land Usage Shape
- Resident Living Standard

41
• Divide total area into unit area(Aij)
• Calculate occurred traffic each
BTS/Sector
• Distribute traffic uniformly within
BTS/Sector coverage
• Decide weighting factor each unit
area (Wij) ( Σ Wij = 1)
• Distribute the traffic of target year
to unit area with weighting factor
 Coverage Design and
Dimensioning
1
2
3
j
n
1 2 3 i m
Wij
Site B Site D
W11 W12 W13
W21 W22 W23
W32 W33W31
Wnm
Site C
Traffic Weighting Map(Competitor In Service)
• Additional Factor to be
Considered
• BTS / Sector Traffic

42
Site Acquisition result CellPLAN simulation Result Plot Antenna azimuth & Tilt Degree
- Detail Cell site position - Forward Coverage Plot
- No. of Site Acquisition - Reverse Coverage Plot Initial Overhead Power setup
- Cell site type Decision (Including FMC & RF Repeater)
(BTS, FMC, RF Repeater)
MAP DATA
CellPLAN Tool
- SKTelecom Design Tool
- Detail coverage simulation
(Iterative coverage Simulation)
Result of Design on the MAP
- Anchor site position result
- each site position, etc
Site Acquisition & Simulation(Iterative)
- Search area ring setup for each cell site
(SAR: one of fourth area per cell radius)
- Making the candidate site list survey
- Visit the candidate site
Site Acquisition & Simulation(Iterative)
- Check the cell site qualification
(LOS, Building Rent or room, etc)
- Antenna azimuth & tilt degree decision
CellPLAN Simulation
(Iterative & Detail)
- Forward Ec/Io plo
- Reverse Eb/Nt plot
- H/O Region analysis plot
- Mobile ERP plot, etc
Required Data/Tool
Main Activity
Accomplishment
Stage 3: Coverage Design Ⅱ

43
Site Acquisition
Site Acquisition Procedure
Pre-visit Analysis and
Rank Candidate Sites
All Sites
Unacceptable
Visit Sites
Perform and Evaluate
Drive Test
Notify Real Estate
Visit Search Area
Revise Objectives
Redesign System
Release SAMs for Site
Search
YES
NO

44
Site Acquisition
 Pre-visit analysis and rank the candidate sites
 The first of the site acquisition is to identify multiple candidates
for each site location, evaluate them on various criteria and rank
them accordingly. This procedure results in identification of the
best suited candidates for all sites. If all the candidates for any site
are rejected for any reason(s), alternatives have to be found, or the
objectives revised and candidates reevaluated, and,if all else fails,
redesign the system/partial system.
 The ranking of the candidate is done in two steps
- A preliminary ranking and visit to the top three
candidates,followed by the final ranking. Approval is then given to
up to three Candidates and the first site that passes the drive test,
if required, is accepted.

45
Site Acquisition
 Select the Anchor Sites(initial design stage)
 Anchor sites dictates the overall RF network design. They
determine the rest of the search rings. Generate an initial cell site
layout, starting with anchor cells and using the preferred/desired
locations and the pre-qualified site candidates.
 Setup the Search Area Ring
 Search rings define the areas where a need for antenna
placement has been determined. Search rings are not precise cell
site locations.
 Prepare a list of candidates to visit
 Since it is not possible, nor necessary, to visit all the candidate sites,
the top two or three candidates from the first part of the ranking matrix
are to be visited. Since a site cannot be acquired unti11 it is visited, it is in
the interest of speedy acquisition that the best potential candidates be
visited

46
Site Acquisition
 Site Visit Activities
 CHECK LOCATION DATA, using the maps or GPS. And record it
 CHECK OBSTRUCTIONS in all directions, e.g. tall building,
unobstructed line of sight for microwave propagation, airports,
other antennas, AM stations, etc.
 ORIENT THE ANTENNA using a compass. Getting an orientation
degree is important to evaluate the coverage effectiveness of this
site
 TAKE MEASUREMENT of distance between equipment shelter
and antennas (cable run), dimensions of the equipment shelter
and compared to the dimensions of the vendor equipment.
 TAKE PICTURES to document intervening structures/unusual
topography of the site.

47
Site Acquisition
 Redesign of the system
 In the event that all sites initially recommended by Real Estate
are unacceptable, reevaluation of rejected sites is not feasible and
no alternatives can be identified, the recourse is to revise
objectives and redesign the system if needed. This process is
initiated by forwarding the Redesign Request to RF Engineering,
identifying the reason(s) why this situation arose, and, upfront,
making some suggestions or issues to bear in mind while
redesigning the system. This facilitates a successful redesign, with
less chances of again yielding unacceptable candidates.

48
Coverage Simulation
• Measurement Integration
• Forward Link Analysis
- RSSI
- Pilot Ec/Io
- Soft Handoff
•Reverse Link Analysis
- Mobile ERP
- Traffic Eb/Nt
• GIS DB
- Terrain
- Morphology
- Vector
- Building
• Propagation Prediction Model
• Field Measurement Data
• Cell Site Parameters
• Traffic Distribution
CDMA Cellular
Wireless Network
Analysis
Personal Computer
Window 95
CellPLAN
CellPLAN Structure

49
Coverage Simulation
 Main Activities
 Forward Coverage Analysis
Forward Pilot Ec/Io Plot
Forward Pilot Best Server plot
Forward Pilot Eb/Nt plot
 Reverse Coverage Analysis
Reverse Traffic Eb/Nt plot
Reverse Mobile ERP Plot
 Soft Handoff region ratio and Analysis
 CDMA Forward/Reverse Link Coverage Analysis
 2D/3D profile for LOS check, etc

50
PN Offset Allocation Result Paging zone Decision H/O Neighbor list simulation
- PILOT_INC Decision - Paging channel capacity calc. - make the H/O neighbor list
- PN Offset Reuse Distance Calculation - Paging zone decision
- Cell site PN Offset Allocation BTS O/H Power Simulation
Design Criteria
- PILOT Assignment
- Soft Handoff Region ratio
- Paging channel capacity
- Paging zone
Cell Plan Tool
- Handoff simulation
- coverage simulation, etc
PN Offset Allocation
- PILOT_INC Calculation
(Lower/Upper Limit)
- PN Offset Reuse Distance Calculation
- Base Station PN Offset Allocation
Paging Zone Decision
- Paging Channel Capacity Calc.
- Paging Zone Decision
Handoff Neighbor List Simulation
- Handoff neighbor list
BTS Overhead Power Simulation
Required Data/Tool
Main Activity
Accomplishment
Stage 4: Parameter Design

51
- PN offset allocation
- Paging zone
- Handoff neighbor list
- Overhead power
• Use coverage design result and design criteria
• Design results are used the initial operation value of system
parameters
• Adjust the system parameters according to optimization after
system in-service
• Designed parameters
Parameter Design

52
Parameter Design (Pilot offset allocation)
Lower Limit for
PILOT_INC
No interference Condition between δ1 and δ2
1. To prevent the presence of a pilot signal with
a different PN offset in the active search window
due to a large differential delay
2. To prevent the presence of a pilot signal with
an undesired PN offset in the neighbor search
window due to a large differential delay
ri : Cell radius
δi : Pilot PN Phase offset
τi : Time delay between Cell site and Mobile station
SA
: active search window size (one sided)
SN
: neighbor search window size(one sided)
PILOT Interference between sites
p1
p2
Interference
p
r1 chips
r2 chips
PN Offset = δ2 chips
PN Offset = δ1 chips

53
δ1
δ2
α1+τ1 δ2 +τ2
sA
Cell Tx PN timing
Mobile Rx
PN timing
Active Search
WindowEarliest arriving
multipath of a pilot
Condition 1
(δ2 + τ2) - (δ1 + τ1) >SA
δ12 = δ2 - δ1 > SA
+ max{τ1 - τ2}
max{τ1 - τ2} = r1
δ1+τ0 δ2 +τ0
sN
Mobile Rx
PN timing
Earliest arriving
multipath of a pilot
Condition 2
δ0+τ0 δ1+τ1
δ2 +τ2
sA
sN
Neighbor Search
Window
δ2 + τ0 - SN
> δ1 + τ0 + SN
δ12 = δ2 - δ1 > 2SN
δ12 = δ2 - δ1 > max{SA
+ r1, 2SN
}
δ12 = PILOT_INC * 64
PILOT_INC * 64 > 2 SN
(
SN >
SA
,SN
> r1)
sN
sN

54
Pilot PN Offset Reuse
Pi : cell site Tx Power
di : Distance between Cell site and MS
γi : Pathloss exponent
di : Distance between cell sites
T : Threshold value
PILOT PN OFFSET REUSE
Cell 3
r3 chips
Cell 1
r1 chips
Phase Offset = δ1 chips Phase Offset = δ1 chips
Cell 2
r2 chips
D chips
Phase Offset = δ2 chips
No interference Condition between δ1 and δ2
1. To prevent undesired finger output for the pilot
signal from distant reuse cell
2. To guarantee the absence of the undesired finger
output for the pilot signal from distant reuse cell
3. To prevent indistinguish ability of sectors with the
same offset in other’s neighbor search window

55
Condition 1
D > 6.8r
Condition 2
If d1=r1, d3=D-r1 (Worst case)
e
d
d
P
P b
T •
−
>







 )(
1
3
3
1 31
ξξ
γ
β
γ
ξξ
1
)(
3
1
1
311








••+>
−
e
P
Pr
b
TD
β
τ3 - τ1 >SA
If τ1=r1, τ3=D-r1
D > 2r + SA
Condition 3
To distinguish the cell1, cell 3 at the cell 2, must keep
the distance above 2r2 + s2N
In case of straight line of three cell sites(worst case)
D > 2(2r2 + s2N
)
Equal size sells & Power
γ = 3.84, T = 19dB
8dB stdev for the shadow fading
D > MAX(condition1, condition2, condition3)
> MAX(condition1, condition3)
Reuse Distance

56
Parameter Design (Paging channel analysis)
General Assumption
Numerical
Value
General Assumption
Numerical
Value
a. Paging Channel Capacity 9600 bps j. System Parameter Message 264 bits
b. Maximum allowable utilization 0.9(90%) k. Access Parameter Message 184 bits
c. Paging Strategy(No. of users) 2 l. Neighbor List Message 216 bits
d. Termination Rate 0.35 m. CDMA Channel List Message 88 bits
e. Busy Rate 0.03 n. Extended System Parameter Message 112 bits
f. BHCA per Subscriber 2 o. Channel Assignment Message 144 bits
g. Number of Sectors per MSC ----- p. Order Message
h. General Page 136 bits
Voice Mail Service
q. Voice Mail Notification 720 bits
i. Overhead Message I=j+k+l+m+n
Short Message Service
r. Data Burst Message(x: No. of
character) 7x+380 bits
s._DONE Message 72 bits
Assumption & Paging channel MSG Lengths

57
Parameter Design (Paging channel analysis)
1 Pagi ng Capaci t y Anal ysi s Tabl e
2 Si ze
3 Number Of Users 200000 Subscri bers
4 Number of power Up/ Down per day 5
5 Ti mer based Regi st rat i on peri od paramet er 64 Ti me Based Regi st rat i on Peri od
6 TI mer based Regi st rat i on peri od val ue - Second 5242. 88
I F(POWER(2, (C5/ 4))*0. 08= 0. 08, 0, POWER(2, (C5/ 4))*0. 08) :
Typi cal Val ue of Reg. Peri od
7 Anot her Regi st rat i on 0 Zone-based Reg. Et c
8
9 Number of Zones 1 1 z
10 Number of BTS per Zone 24. 00
11 Number of Sect ors per BTS 3
12 Number of BTS i n Syst em 24
13 Sect ors i n Syst em 72 C11*C12
14 Regi st rat i on
15 Tot al Regi st rat i on i n t he Syst emper Day 5295898
C3*(C4*2+3600*24/ C6+C7) : Power On/ Of f , Ti me Based, Zone
based r
16 Concent rat i on rat e of BHCA 0. 098

58
Parameter Design (H/O neighbor list)
• make the H/O neighbor list by using CellPLAN tool.
(Maximum List: 20 EA / Cell Site)
• 1st
, 2nd
Cluster analysis(1,2 tier analysis)
• Search Window Size decision
- Active Search Window Size
- Neighbor Search Window Size
- Remaining Search Window Size

59
Yearly based Dimensioning result
- Required BTS no. - Required FA no.
- Required CHC no.
- Required channel element no.)
Marketing Demand Analysis
- Subscriber forecasting
- MOU(Minute of Usage)
- Traffic prediction
Equipment Type
- capacity per equipment
- coverage per equipment
Cell site traffic
Distribution analysis
Engineering sheet Drawing Up
- FA growth calculation
- Channel Card quantity
- Channel element quantity
Engineering sheet Drawing Up for
yearly based dimensioning
- No. of Required FA
- No. of Required Channel Element
- No. of Required CHC(Channel Card)
Required Data/Tool
Main Activity
Accomplishment
Stage 5: Dimensioning

60
Dimensioning Procedure
Design Criteria
- MAX. CE per FA
- MIN. CC
- GOS(Blocking Rate)
Estimated Traffic
- Carried Traffic
- Soft Handoff Traffic
Cell Site Configuration
- Channel Card Type
- BTS Type
FA Dimension
BTS Dimensioning
Loading
Calculation
Module
Required CE Calculate
Required CE
Calculation
Module
Required CC CalculateCE per CC

61
Predicted Traffic Calculation by Subscriber’s
MOU Analysis
• Total Traffic and Traffic per Sub. Calculation
- Erlang / Sub. = MOU per Sub. / ACDM * BHDR / MH
- Total Erlang = Erlang / Sub. * Total Estimated Sub.
BHDR : Busy Hour Day Ratio
ACDM : Average Calling Days per Month(Use 26 or 27 days)
MH : Minutes per Hours(60 Minute)
• The Required BTS by the year
• The Required FA No.
• The Required CE and CHC calculation
Engineering Sheet Drawing up

Rf network design

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