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HUAWEI Confidential

GSM Abis Dimensioning

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Traditional Transmission——Abis of TDM over E1

Abis E1 Dimension Principle for FullRate:

15 FR TRX per E1

S555 configuration: 1 BCCH per cell; 3 SDCCHs per cell; TCH channel = 5*8-1-3=36 Signaling : 1 RSL / TRX, 1 OML / Site, RSL or OML occupy one 16kbps timeslotTotal 16kbps channel required= 36*3+15+1=124= 124/4=31 64kpbs timeslot= 1 E1

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Abis E1 Dimension Principle for HalfRate:

About 13 100％HR TRX per E1

About (15-2*HR Ratio) TRX per E1

Traditional Transmission——Abis of TDM over E1

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Transmission Optimization——Abis of IP over E1

Abis Interface ThroughputAbis Interface Throughput

Control Plane Throughput

Control Plane Throughput

User Plane ThroughputUser Plane Throughput

T _Control PlaneT _Control Plane T _User PlaneT _User Plane

Abis throughput factors:Ø Signalling Overhead in control planeØgeneral consider signaling throughput is equal to 10% CS user throughput

Dimensioning Procedure:

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L1（PHY）

IP

UDP

MAC

RSL/OML

LAPD

Control PlaneControl Plane User PlaneUser Plane Payload (bits)

Payload ( MAC Layer)

264

Internal defined header

32

IP_UDP header 224

PPP header 56

Voice frame len / 20ms (bit)

576

IP

UDP

Transmission Optimization——Abis of IP over E1

Abis Interface Protocol Stack (IP over E1) Protocol Overhead in user plane-CS part

PPP

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Dimensioning Procedure - User Plane

Voice frame len / 20ms (bit) =Payload ( MAC Layer) + internal defined header + IP_UDP header + PPP header=576 bits

Voice frame len / 20ms (bit) =Payload ( MAC Layer) + internal defined header + IP_UDP header + PPP header=576 bits

INPUT• VAD Factor = 0.5• MAC Packet Size = 264 bits• Packet time = 20ms

• VAD Factor = 0.5• MAC Packet Size = 264 bits• Packet time = 20ms

Voice frame bit rate / UM channel（kbps）W/O Mux=voice frame len / 20ms (bit) * 50 * VAD / 1024=14.1kpbs

Voice frame bit rate / UM channel（kbps）W/O Mux=voice frame len / 20ms (bit) * 50 * VAD / 1024=14.1kpbs

Transmission Optimization——Abis of IP over E1

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Avg frame bit rate (kbps) with MUX=Mux total size*50*VAD factor/1024/Mux number=8.8kbps

Avg frame bit rate (kbps) with MUX=Mux total size*50*VAD factor/1024/Mux number=8.8kbps

Mux Total Size (bit) with MUX=8*(Payload ( MAC Layer)+56) + internal defined header + IP_UDP header + PPP header=2872

Mux Total Size (bit) with MUX=8*(Payload ( MAC Layer)+56) + internal defined header + IP_UDP header + PPP header=2872

Maximum MUX number = 8Maximum MUX number = 8

End of CS User Plane

Dimensioning Procedure - User Plane

Transmission Optimization——Abis of IP over E1

speech version(Code Scheme)

Payload in RLC/MAC layer (bit）

Avg frame bit rate(kbps)

FR 264 8.8

EFR 248 8.4

AMR-FR12.2 264 8.8

HR 120 5.2

AMR-HR7.95 176 6.6

CS-1 160 6.4

CS-2 240 8.4

CS-3 288 9.5

CS-4 400 12.3

MCS-1 176 6.8

MCS-2 224 8.0

MCS-3 296 9.7

MCS-4 352 11.1

MCS-5 448 13.5

MCS-6 592 17.0

MCS-7 896 24.4

MCS-8 1088 29.1

MCS-9 1184 31.4

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Example - Abis of IP over E1

CS channel bandwidth (Kbps)=(1-LCLS percentage)*Avg frame bit rate (kbps) with MUX for CS* Total voice number/BH=(1-10%)*8.8*84=665.28 kbpsPS channel bandwidth (Kbps)=Number of Activated PDCHs in Busy Hours*Avg frame bit rate (kbps) with MUX for PS=3*31.4=97.2kbpsSignaling bandwidth (Kbps)=10% *CS channel bandwidth (Kbps)=10%*665.28=66.53kbpsTotal Abis requirement (Kbps)=(CS channel bandwidth (Kbps)+ PS channel bandwidth (Kbps)+ Signaling bandwidth (Kbps))/Transmission Link Bandwidth Utilization=(665.28+97.2+66.53)/85%=975.31kbpsTotal Abis timeslot requirement (64Kbps)=Roundup (Total Abis requirement (Kbps)/ 64kbps,0)+1=Roundup(975.31/64,0)+1=17

Dimensioning Procedure Case study: supposed S444; 10% LCLS; 100% FR; 3 Activated MCS9 PDCHs; 85%Transmission Link Bandwidth Utilization

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Abis Dimensioning for S111 ConfigurationAssumption1: (1) S111; (2) 10% LCLS; (3) 20% HR; (4) 2 Activated MCS9 PDCHs;(5) 85%Transmission Link Bandwidth Utilization

Transmission Method Abis Bandwidth (Kbps)

Abis IP over FE/GE 379.62

Abis IP over E1/T1 326.32

Assumption2: (1) S111; (2) 10% LCLS; (3) 20% HR; (4) 2 Activated DAS-12 PDCHs (EDGE+);(5) 85%Transmission Link Bandwidth Utilization

Transmission Method Abis Bandwidth (Kbps)

Abis IP over FE/GE 494.47

Abis IP over E1/T1 402.89

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