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4. Design Methodology
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Design Workflow
Equipment Selection
Antenna Placement
Coverage Area
Estimation
Schematics
Link BudgetCalculation
Does the designmeet customers
requirement ?
Design Estimation
Complete
Verify Customers
Design Criteria
Y
N
Site Survey
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Design Criteria Example 2
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Site Survey
Bu i ld ing Informat ion Coverage Requ iremen t
Cable Rou t ing Info rmat ion
Equipment Locat ion Requ irement Electr ical Requ iremen t
E1/T1 Requ irement
Checklis t IBS01
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Site Survey
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System Design
Transm ission Test Equipm ent Select ion
Coverage A rea Est imat ion
Antenna Placement Schematics Diagram
Link Budget Analys is
Checklis t IBS02
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System Design
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Coverage Area Estimation
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Antenna Placement
Carr ied out b ased o n the Coverage Area Estimation andTransm iss ion Test Data (if any)
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Schematics
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EIRP Table
ANTCoverage
TypeOutput Before
CombinerCombining
LossTotal Loss ANT Gain ANT Port ANT EIRP
Common
Area / Lift
900
MHz
(dBm)
1800
MHz
(dBm)
2100
MHz
(dBm)
GSM
900
DCS
1800
WCDM
A
2100
900
MHz
(dB)
1800
MHz
(dB)
2100
MHz
(dB)
900
MHz
(dBi)
1700-
2200
MHz
(dBi)
900
MHz
(dBm)
1800
MHz
(dBm)
2100
MHz
(dBm)
900
MHz
(dBm
)
1800
Mhz(
dBm)
2100
MHz
(dBm
)
ANT1-20F lift 38.45 38.45 33 0.6 0.6 0.6 25.8 27.5 28.1 2 4 12.6 11.0 4.9 14.6 15.0 8.9
ANT2-20F common area 38.45 38.45 33 0.6 0.6 0.6 26.3 28.1 28.7 2 4 12.2 10.3 4.4 14.2 14.3 8.4
ANT3-20F common area 38.45 38.45 33 0.6 0.6 0.6 26.7 28.4 29.1 2 4 11.8 10.0 3.9 13.8 14.0 7.9
ANT4-20F lift 38.45 38.45 33 0.6 0.6 0.6 32.5 34.2 34.7 2 4 6.0 4.3 -1.7 8.0 8.3 2.3
ANT5-20F common area 38.45 38.45 33 0.6 0.6 0.6 26.6 28.3 28.9 2 4 11.9 10.2 4.1 13.9 14.2 8.1
ANT6-20F common area 38.45 38.45 33 0.6 0.6 0.6 26.3 28.1 28.7 2 4 12.2 10.3 4.4 14.2 14.3 8.4
ANT7-20F lift 38.45 38.45 33 0.6 0.6 0.6 25.8 27.5 28.1 2 4 12.6 11.0 4.9 14.6 15.0 8.9
ANT1-19F common area 38.45 38.45 33 0.6 0.6 0.6 27.8 29.4 29.9 2 4 10.6 9.0 3.1 12.6 13.0 7.1
ANT2-19F lift 38.45 38.45 33 0.6 0.6 0.6 28.6 30.6 31.2 2 4 9.8 7.9 1.8 11.8 11.9 5.8
ANT3-19F common area 38.45 38.45 33 0.6 0.6 0.6 27.9 29.6 30.1 2 4 10.5 8.8 2.9 12.5 12.8 6.9
ANT4-19F common area 38.45 38.45 33 0.6 0.6 0.6 28.2 29.9 30.4 2 4 10.3 8.5 2.6 12.3 12.5 6.6
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ANT PL(d0) d n10n
log(d/d0)Lw LNF Rx Level Design Level
Excess
Margin
900
MHz
(dB)
1800
MHz
(dB)
2100
MHz
(dB)
(m) (dB)
900
MHz
(dB)
1800
MHz
(dB)
2100
MHz
(dB)
(dB)
900
MHz
(dB)
1800
MHz
(dB)
2100
MHz
(dB)
900
MHz
(dBm
)
1800
MHz
(dBm
)
2100
MHz
(dBm
)
900
MHz
(dB)
1800
MHz
(dB)
2100
MHz
(dB)
ANT1-20F 31.5 37.6 38.4 10.0 3.0 30.0 6 6 8 10 -62.9 -68.6 -77.5 -75.0 -75.0 -85.0 12.1 6.4 7.5
ANT2-20F 31.5 37.6 38.4 12.0 3.0 32.4 6 6 8 10 -65.7 -71.6 -80.4 -75.0 -75.0 -85.0 9.3 3.4 4.6
ANT3-20F 31.5 37.6 38.4 12.0 3.0 32.4 6 6 8 10 -66.1 -72.0 -80.8 -75.0 -75.0 -85.0 8.9 3.0 4.2
ANT4-20F 31.5 37.6 38.4 9.0 3.0 28.6 6 6 8 10 -68.1 -73.9 -82.7 -75.0 -75.0 -85.0 6.9 1.1 2.3
ANT5-20F 31.5 37.6 38.4 12.0 3.0 32.4 6 6 8 10 -66.0 -71.8 -80.7 -75.0 -75.0 -85.0 9.0 3.2 4.3
ANT6-20F 31.5 37.6 38.4 12.0 3.0 32.4 6 6 8 10 -65.7 -71.6 -80.4 -75.0 -75.0 -85.0 9.3 3.4 4.6
ANT7-20F 31.5 37.6 38.4 10.0 3.0 30.0 6 6 8 10 -62.9 -68.6 -77.5 -75.0 -75.0 -85.0 12.1 6.4 7.5
ANT1-19F 31.5 37.6 38.4 12.0 3.0 32.4 6 6 8 10 -67.2 -73.0 -81.7 -75.0 -75.0 -85.0 7.8 2.0 3.3ANT2-19F 31.5 37.6 38.4 10.0 3.0 30.0 6 6 8 10 -65.7 -71.7 -80.6 -75.0 -75.0 -85.0 9.3 3.3 4.4
ANT3-19F 31.5 37.6 38.4 12.0 3.0 32.4 6 6 8 10 -67.4 -73.1 -81.9 -75.0 -75.0 -85.0 7.6 1.9 3.1
ANT4-19F 31.5 37.6 38.4 12.0 3.0 32.4 6 6 8 10 -67.6 -73.5 -82.2 -75.0 -75.0 -85.0 7.4 1.5 2.8
EIRP Table (contd.)
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Uplink Noise Figure Calculation
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Uplink Link Budget Analysis
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Uplink Link Budget Analysis
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EMR Safety
ICNIRP standard has set 2 MPE lim its : Publ ic expos ure (unc ontro l led environment)
Occupat ional exposu re (con tro l led environment)610
510
410
310
100
10
0.1
1.0
01.0
2mW/cm
3 10 30 100 300 3 10 30 100 300 3 10 30 100 3001 1
kHz MHz GHz
E
H
Reference Levels
Time and Whole Body Averaged
f in MHZ
= Occupational
= General Public
100 /f 2
20/f 2
2 /ff / 2000
f /400
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ICNIRP MPE Standard
From the ICNIRP graph, the levels o f power dens ity fo r General
Publ ic are:
System Power Density
(mW/cm2)
Power Density
(W/m2)
GSM900 0.045 4.5
GSM1800 0.09 9.0
WCDMA2100 0.10 10
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Theoretical Safe Distance
The theoret ical m inim um safe distanc e for an N-carrier
transm it ter can be der ived from th e free space power densityexpression
Expressing in terms o f minimum safe distance
24 r
EIRPNPd
mP
EIRPNr
d
4
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Minimum Safe Distance
Minimum safe distance can be calculated b y u sing the highest
EIRP value of the antenna ob tained dur ing l in k bu dget
calculat ion,
For example, if the maximum EIRP is 11.4dBm and 8.1dBm for
GSM900 and UMTS2100 respectively , then:
System EIRP(dBm)
EIRP(mW)
N Pd(W/m2)
Safe Distance(m)
GSM900 11.4 13.8 4 4.5 0.031
WCDMA2100 8.1 6.5 2 10 0.010