BSC6900 GSM V900R012 Dimensioning

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Note instruction

Confidential Information of Huawei. No Spreading Without Permission

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Impacts of the IP Transformation

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The Abis interface supports the traditional TDM mode, IP transformation. The transmission mode of the Abis interface is not related to the structure (BM/TC separated modeBM/TC combined mode, A IP mode) of the A interface. A built-in PCU or an external PCU can be configured for the BSC. When an external PCU is configured, the BSC does not support PS services in cells using IP transformation

When the A interface adopts IP transformation, the TC function is moved to MGW. The A interface using IP requires that the CN uses a softswitch-based structure, and the MSC server and MGW are reconstructed. It is not related to the Abis interface, PCU (internal or external), or Gb interface.


If the MSC and the BSC are in different central equipment rooms, place the TC resource subrack in the same equipment room as the MSC to save transmission

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resource subrack in the same equipment room as the MSC to save transmission resources. The reason is as follows: The circuits from the TC subrack are standard 64 kbit/s PCM circuits, while the circuits between the business processing subrack and the TC resource subrack adopt 16 kbit/s (full rate voice service) or 8 kbit/s (half rate voice service) voice coding and the 4:1 or 8:1 multiplexing mode. Therefore, remote deployment of TCs can save about 75% to 87.5% transmission resources.

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BHCA: Busy Hour Call Attempts.

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The number of call attempts during the busiest hour of the day. BHCA cover successful calls and unsuccessful call attempts.

Erlang: A unit of measurement of telephone traffic. It is equal to one hour of conversation. It also specifies the approximate

number of trunks in use; for example, if the traffic in a call center is 8.5 Erlangs in one hour, more than 8 trunks were used in that hour. Reference


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Parameter Name Default Value Parameter Explanation

Average voice traffic per subscriber@BH(Erlang) CSErlPerSub 0.02

Average CS traffic per subscriber in busy hours

Average Call Duration(Second) CSCallDuration 60

Average call duration per subscriber in busy hours

Percent of Mobile originated calls CSMOCRatio 50%

Percentage of MO calls in busy hours

Percent of Mobile terminated calls CSMTCRatio 50%

Percentage of MT calls in busy hours

Average LUs/sub/BH CSLUPerSubinBH 1.2Average number of location updates per subscriber in busy hours

Average IMSI Attach/sub/BH CSAttachPerSubinBH 0.15

Average number of IMSI attaches per subscriber in busy hours

Average IMSI Detach/sub/BH CSDetachPerSubinBH 0.15

Average number of IMSI detaches per subscriber in busy hours

Average MO-SMSs /sub/BH CSMOSMSPerSubinBH 0.6

Average number of SMs sent per subscriber in busy hours

Average MT-SMSs /sub/BH CSMTSMSPerSubinBH 1

Average number of SMs received per subscriber in busy hours

Average intra-BSC HOs /sub/BH CSIntraHOPerSubinBH 1.1

Average number of intra-BSC handovers per subscriber in busy hours

Parameters are described in tables. The following table defines the meanings represented by different colors of table cells.

Input parameter, which is input according to the network planning and design results. For an input parameter that has a default value, the default value can be used when the corresponding input parameter of the network is inaccessible. The calculation

result obtained by using the default value deviates from the actual network status. The default value is usually a conservative policy. More resources are required according to the calculation results obtained by using default values.Advanced parameters, for which users can set them or use the default values.

Automatic calculation result.

Percentage of MO calls in busy hours and percentage of MT calls in busy hours: CSMTCRatio =1 CSMOCRatio

subscriber in busy hours

Average inter-BSC HOs /sub/BH CSInterHOPerSubinBH 0.1

Average inter-BSC handovers per subscriber in busy hours

Paging Retransfer Ratio PagingRetransferRatio 35%Paging resending ratio on the A interface in busy hours

Relationship Between CS Traffic Model Parameters

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Average CS traffic per subscriber in busy hours, average call duration per subscriber in busy hours, average number of MO calls per subscriber in busy hours, and average number of MT calls per subscriber in busy hours:

CSMOCPerSubinBH =(CSErlPerSub*3600/CSCallDuration)*CSMOCRatio

CSMTCPerSubinBH =(CSErlPerSub*3600/CSCallDuration)*CSMTCRatio

Parameters of the PS Traffic Model Basic PS traffic model

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Parameter Name Value Parameter Explanation

GPRS Active Sub PSSubAct 10000 Number of online (E)GPRS network subscribers

average traffic per sub in busy hour (bps)

PSTrafficPerSubinBH 300

Average (E)GPRS traffic per online subscriber in busy hours (application layer)

PS Traffic Peak Ratio PSPeakRatio 25%

Proportion of incremental traffic (PS peak traffic exceeding the average traffic) to the average traffic, which can be ignored when it is not needed

average IP packet data length in Gb (Bytes) PayloadLenGb 300

Average packet length on the Gb interface, which can be ignored when it is not needed

The sum of the ratios of all the preceding coding rates should be equal to 100%.

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During the calculation, you can also use the definite average rates to replace these input values.

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BSC and Network Configuration

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Parameter Name Default Value Parameter Explanation

TRX Number TRXNoPerBSC 1600 Total number of TRXs in the BSCTCH/H ratio TCHHRatio 30% Ratio of half rate TCHs

A Erl: Um erl AUmRadio 80%

Ratio of the A-interface CICs to the Um-interface channels. In actual applications, not all cells in the BSC reach the peak traffic at the same time. Therefore, it is unnecessary to set the value of this parameter to 1:1. This value decreases in the following areas: traffic dense area, downtown, suburb, urban, and wide coverage.

TCH/F ratio TCHFRatio 70% Ratio of full rate TCHsStatic PDCH/Cell SPDCHPerCell 1 Number of static PDCHs per cellDynamic PDCH/Cell DPDCHPerCell 2

Maximum number of dynamic PDCHs per cell

SS7 link Bandwidth SS7LinBandwidth 1984 kbps

SS7 link bandwidth: 64 kbit/s or 2 Mbit/s (1984 kbit/s)

Dynamic PDCH Active Ratio

DynPDCHActiveRadio 50%

Ratio of activated dynamic PDCHs in busy hours. The configured PDCHs may be activated or deactivated. Therefore, this parameter is mandatory.

Advanced Input Parameters

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Name Default Value Parameter Explanation

CHPerTRX 7.0 Average number of TCH/Fs per TRX. The value is calculated according to the number of TRXs and the relationship table of cell channel quantity by the following formula: CHPerCell /TRXPerCell.

The number of TRXs and the relationship table of cell channel quantity can be adjusted according to the network optimization strategies of the telecom operator.

CHPerCell 27 Average number of TCH/Fs per cell. The value can be calculated according to the number of TRXs and the relationship table of cell channel quantity. The value can be adjusted according to the network optimization strategies of the telecom operator.

MaxPDCHRatio 50% Ratio of maximum PDCHs in busy hours.

The value can be calculated indirectly by using the following formula:

= (SPDCHPerCell + DPDCHPerCell) x number of cells / number of TCHsCSVAD 50% Voice activation factor, namely, ratio of the valid voice transmission time

to the total call duration. The value ranges from 0 to 1. Usually, the value 0.5 is used.

PSUsage 50% PDCH utilization, namely, the ratio of the data transmission time to the idle time after a PDCH is occupied. (The concept is similar to that of CSVAD.)

E1T1STM1Usage 80% Usage of IP transport resources (E1/STM1). In the IP or HDLC mode, the Abis/Ater/A interface reserves some bandwidth for normal transmission in the case of retransmission or instantaneous burst. This parameter indicates

the case of retransmission or instantaneous burst. This parameter indicates the utilization of the bandwidth that can be allocated.

FEGEUsage 80% Usage of IP transport resources (FE/GE). In the IP or HDLC mode, the Abis/Ater/A interface reserves some bandwidth for normal transmission in the case of retransmission or instantaneous burst. This parameter indicates the utilization of the bandwidth that can be allocated.

GEOpticUsage 80% Usage of IP transport resources (GE optic). In the IP or HDLC mode, the Abis/Ater/A interface reserves some bandwidth for normal transmission in the case of retransmission or instantaneous burst. This parameter indicates the utilization of the bandwidth that can be allocated.

GbFRUsage 70% Usage of Gb transport resources (FR). In the Gb FR transmission mode, some bandwidth is reserved for normal transmission in the case of retransmission or instantaneous burst. This parameter indicates the utilization of the bandwidth that can be allocated.

GbIPUsage 70% Usage of Gb transport resources (IP). In the Gb IP transmission mode, some bandwidth is reserved for normal transmission in the case of retransmission or instantaneous burst. This parameter indicates the utilization of the bandwidth that can be allocated.

AbisCICIPbandWidth 36.4 Average IP bandwidth of the Abis-interface CIC. The bandwidth is an average value of the CS, PS, and LAPD signaling bandwidths. When the Abis MUX is disabled, the recommended value is 36.4; when the Abis MUX is enabled, the recommended value is 20. You need to adjust the value manually according to the actual traffic model.

ACICIPbandWidth 39.6 Average IP bandwidth of the A-interface CIC. When the Abis MUX is disabled, the recommended value is 39.6; when the Abis MUX is enabled, the recommended value is 20.2. Adjust the value manually according to the actual traffic model.

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Note:

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TRXPerCell is a network configuration input parameter. If the number of TRXs per cell is not available, you can estimate the number of TRXs per cell by using the following formula:

TRXPerCell = Total TRX/BTS Num/3 Simply assume that each cell is configured with one primary BCCH. In the full

rate mode, every two TRXs share one SDCCH; in the half rate mode, every TRX uses one SDCCH.

TCHHRatio is the input data of the CS traffic model. UmBlockRatio is the input parameter Grade of Service (GoS) on Um

interface in the traffic model. erlangB_traffic(number of channels,block ratio) indicates the ErlangB table

formula used for calculating the cell traffic based on the number of channels and the block ratio.

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The following table lists the BHCA weight of each service type:

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The weight of each service is the percentage of the service obtained through the BSC6900 designs and tests to the traffic transformed from the XPUa/SPUa board performance.

CSLUPerSubinBH, CSAttachPerSubinBH, CSDetachPerSubinBH, CSMOCPerSubinBH, CSMTCPerSubinBH, CSMRPerSubinBH, CSMOSMSPerSubinBH, CSMTSMSPerSubinBH, CSIntraHOPerSubinBH, CSInterHOPerSubinBH, and CSRetransferPagingPerSubinBH are input data of the traffic model.

Service Type CS BHCA WeightLU to CS call 0.3

IMSI Attachs to CS call 0.3IMSI Detachs to CS call 0.3

CS calls to CS call 1.0

MR Reports to CS call 0.008

CS SMS to CS call 0.5Intra-HOs to CS call 0.3

Inter-HOs to CS call 0.4

CS Paging to CS call 0.5

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Note

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The Gb interface throughput is determined by the maximum traffic of all active GPRS subscribers. If the calculation is based on the maximum throughput of all the PDCHs (customers may have this requirement), the calculation result is much greater than that is needed.

PSSubAct, PSTrafficPerSubinBH, and PSPeakRatio are the input data of the PS traffic model.

SubPerBSC and MaxPDCHPerBSC are BSC capacity calculation results.

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Caution: Service links and LAPD signaling links cannot share one 64 kbit/s timeslot.

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he following table lists the number of 16 kbit/s timeslots on the Abis interface occupied per coding scheme.

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occupied per coding scheme.

code scheme Ratio 16k TS number per code scheme

CS1 20% 1

CS2 0% 1

CS3 0% 2

CS4 0% 2

MCS1 0% 1

MCS2 0% 1

MCS3 0% 2

MCS4 0% 2

MCS5 0% 2

MCS6 80% 2

MCS7 0% 3

MCS8 0% 4

MCS9 0% 4

Avg. Abis TS numer

occupied per PDCH1.8

ESL: extended signaling link of the BTS. If the BTS supports Flex Abis, in the case of statistical multiplexing on a 64 kbit/s timeslot, a 64 kbit/s timeslot needs to be

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statistical multiplexing on a 64 kbit/s timeslot, a 64 kbit/s timeslot needs to be assigned to the ESL. In this case, the ESL is always multiplexed with the OML in the 64 kbit/s timeslot. In the case of physical multiplexing on a 16 kbit/s timeslot, no timeslot is assigned to the ESL. In this case, the ESL shares the same timeslot with the OML.

Note

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By default, the multiplexing ratio of Abis interface signaling links is 4:1, that is, four RSLs or OMLs share 64 kbit/s bandwidth.

For HR traffic, the multiplexing ratio of Abis interface signaling links is 2:1, that is, two RSLs or OMLs share 64 kbit/s bandwidth.

For satellite transmission, the Abis interface uses 16 kbit/s LAPDs, and one RSL or OML occupies 16 kbit/s bandwidth.

SiteNoTDME1, TRXNoTDME1 and AbisLAPDMultiRate are input parameters for BSC and network configuration.

For FR traffic, the value of TrxNumPerE1 is set to 15; for HR traffic, the value of TrxNumPerE1 is set to 13.

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TrxNumPerE1 is set to 13.

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Note:

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ABlockRatio is the input parameter Grade of Service (GoS) on A interface in the traffic model.

CSErlPerBSC is the BSC capacity calculation result.

There are two types of signaling links in the SS7 network: 64 kbit/s signaling link and 2 Mbit/s signaling link. The 2 Mbit/s signaling link consists of the standard 2048 kbit/s

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2 Mbit/s signaling link. The 2 Mbit/s signaling link consists of the standard 2048 kbit/s link and the N x 64 kbit/s (1 < N < 32) link.

To meet the signaling requirements for large traffic volume, two signaling transmission schemes can be used in the BSC6900.

Multiple local signaling points: The BSC6000 supports up to 4 local signaling points, enabling 64 signaling links over the A interface.

2 Mbit/s signaling link: The maximum bandwidth of each high-speed signaling link can be 1984 kbit/s

Note G ranges from 0.2 to 0.4. M and L vary with the values defined in the traffic model. Generally, e is provided by the network operator. Generally, T is 60 seconds.

C = G*8192*T/(E*M*L) = G*8192*60/(0.7*475.8) = G*1475.77

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If G = 0.2 , one 64K SS7 link can carry 296 CICs in A interface If G = 0.25 , one 64K SS7 link can carry 369 CICs in A interface If G = 0.3 , one 64K SS7 link can carry 443 CICs in A interface If G = 0.4 , one 64K SS7 link can carry 590 CICs in A interface

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The following table lists the example for calculating the number of SS7 links in accordance with the traffic model being adopted.

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Basic Data Value UnitNormal load of SS7 links 0.3 ERL/link

Traffic Model Value UnitTraffic per user in busy hours 0.02 ERLAverage time of a call 60 sRatio of the originated calls 50% /Ratio of the terminated calls 50% /Number of originated calls in busy hours (A1) 0.6 time/ subscriberNumber of terminated calls in busy hours (A2) 0.6 time/ subscriberNumber of location update in busy hours (A3) 1.2 time/ subscriberNumber of inter-BSC handovers (A4) 0.1 time/ subscriberNumber of intra-BSC handovers (A5) 1.1 time/ subscriberNumber of short messages sent in busy hours (A6) 0.3 time/ subscriberNumber of short messages received in busy hours (A7) 0.5 time/ subscriber

Basic Data of the A Interface TDM ValueIP Value Unit

Average bytes of the messages in an originated call procedure (B1) 287

615 BytesAverage bytes of the messages in a terminated call procedure (B2) 334

662 Bytes

Average length of the signaling unit = A1 x B1 + A2 x B2 + A3 x B3 + A4 x B4 + A5 x B5 + A6 x B6 + A7 x B7 )/(number of originated calls in busy hours + number of terminated calls in busy hours)

procedure (B2) 334 BytesAverage bytes of the messages in a location update procedure (B3) 172

418 BytesAverage bytes of the messages in an inter-BSC handover procedure (B4) 232

396 BytesAverage bytes of the messages in an intra-BSC handover procedure (B5) 34

75 Bytes

Average bytes of a short message sent by an MS (B6) 450 696 BytesAverage bytes of a short message received by an MS (B7) 486 732 Bytes

Average Length of the Signaling Unit TDM Value IP Value Unit

ML 580.5 1218 Bytes

Number of 64 kbit/s SS7 links = system traffic volume x average length of the signaling unit/8192/average time of a call/ normal load of SS7 links

Number of 64 kbit/s SS7 links configured for the system = min [number of broadband SS7 links, (number of GMPSs + number of GEPSs) x 16]

16: the maximum number of 64 kbit/s SS7 links supported by each signaling point of the BSC6900

Number of broadband SS7 links = (system traffic volume x average length of the signaling unit/8192/average time of a call/ normal load of SS7 links) x 64/bandwidth of the SS7 links

Number of broadband SS7 links configured for the system = min [number of broadband SS7 links, (number of GMPSs + number of GEPSs) x 6]

6: the maximum number of the external broadband SS7 links supported by each GMPS/GEPS of the BSC6900

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System Traffic Volume (Erl)

Number of 64 kbit/s SS7 Links

Number of BMs (GMPS + GEPS)

Number of 64 kbit/s SS7 Links Configured for the System

3000 16 1 16 6000 32 2 32 9000 48 3 48 12000 63 4 63

System Traffic Volume (Erl)

Bandwidth (kbit/s) of the Signaling Link

Number of Broadband SS7 Links

Number of BMs (GMPS + GEPS)

Number of Broadband SS7 Links Configured for the System

3000 256.0 4.0 1 4 6000 256.0 8.0 2 8 9000 256.0 12.0 3 12 12000 512.0 8.0 4 8

Note:

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When the total number of A interface CICs is greater than and equal to 4,096, configure a 64 kbit/s SS7 link for every 256 A interface CICs.

When the total number of A interface CICs is less than and equal to 4,096, to ensure that the bandwidth is allocated evenly to each SS7 link, configure a 64 kbit/s SS7 for every 256 A interface CICs and round up the result to 2, 4, 8, 16, or 32.

Note:

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The Gb interface throughput is determined by the maximum traffic of all active GPRS subscribers. If the calculation is based on the maximum throughput of all the PDCHs (customers may have this requirement), the calculation result is much greater than that is needed.

PSSubAct, PSTrafficPerSubinBH, and PSPeakRatio are the input data of the PS traffic model.

SubPerBSC and MaxPDCHPerBSC are BSC capacity calculation results.

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The value of GbTputPerBSC is obtained through the calculation of the overall capacity of the BSC.

1% indicates the average retransmission ratio of Gb interface packets. PayloadLenGb is an advanced parameter. 53 indicates the length of an FR packet header when the Gb interface uses

the FR. UsPer64kpbs indicates the valid number of bytes carried in each 64K timeslot

in the FR mode. The value is 35 k averagely GbFRUsage is an advanced parameter.

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Gb over FR Transmission Usage: 70%The ratio of effective transmission over the Gb interface to the actual physical transmission. Factors such as the retransmission

Gb interface to the actual physical transmission. Factors such as the retransmission rate, peak-to-average burst flow ratio, and signaling overhead rate should be considered in the transmission usage)

Gb Configuration Calculation (FR)

Gb Configuration Calculation (FR)Data Throughput Demand at the IP Layer of the PS Subscriber (kbit/s) 300000*300/1024=87,891

Number of 64 kbit/s Timeslots Supported per GEPUG 31*32=992

IP Bearer Rate per 64 kbit/s Timeslot on the Gb Interface (kbit/s) 200/(200+53)*0.7*64=35Rounded number of 64 kbit/s timeslots that need to be configured on the Gb interface (main board) 87891/35=2511Rounded number of E1s that need to be configured on the Gb interface (main board) 2511/31=81Rounded number of active/standby GEPUGs that need to be configured 2*(81/32)=6

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After Abis over IP is applied, the signaling plane uses the LAPD over UDP/IP protocol stack to carry signaling and the user plane uses the PTRAU over UDP/IP protocol stack to carry speech signals

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speech signals The header length of different layer (CS Part)

TRAU frame: speech payload, including voice and Cbit. The size of the TRAU frame varies with coding schemes.

PTRAU header: four bytes. UDP header: UDP header in the IP speech packet; eight bytes. IP header: IP header in the IP speech packet; 20 bytes. MAC header: The IP speech packet is encapsulated at the data link layer. The MAC

header consists of the source MAC address, destination MAC address, and type. The size of the MAC header is 14 bytes.

MAC CRC: The check performed at the data link layer. The size of the MAC CRC is 4 bytes.

MAC preamble and start delimiter: eight bytes in total with seven bytes of preamble and one byte of start delimiter.

Inter-frame spacing: The spacing between MAC frames. The inter-frame spacing is 12 bytes.

The header length of different layer (PS Part) RLC/MAC data blocks: The size varies with coding schemes. TRAU in-band control signaling: eight bytes. PTRAU header: four bytes. UDP header: UDP header in the IP packet; eight bytes. IP header: IP header in the IP speech packet; 20 bytes. MAC header: The IP speech packet is encapsulated at the data link layer. The MAC

header consists of the source MAC address, destination MAC address, and type. The size of the MAC header is 14 bytes.

MAC CRC: The check performed at the data link layer. The size of the MAC CRC is 4 bytes.

MAC preamble and start delimiter: eight bytes in total with seven bytes of preamble and one byte of start delimiter.

Inter-frame spacing: The spacing between MAC frames. The inter-frame spacing is 12 bytes.

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the size (in bytes) of the TRAU frame in different speech versions

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Speech Version Speech Rate (kbit/s) Size of TRAU Frame (Bytes)

FR 13kbps 33

HR 5.6kbps 15

EFR 12.2kbps 31

AMR 12.2kbps 33

AMR 10.2kbps 28

AMR 7.95kbps 22

AMR 7.40kbps 21

AMR 6.70kbps 19

AMR 5.9kbps 17

AMR 5.15kbps 15

AMR 4.75kbps 14

AMR(HR) 7.95kbps 22


AMR(HR) 7.40kbps 21

AMR(HR) 6.70kbps 19

AMR(HR) 5.9kbps 17

AMR(HR) 5.15kbps 15

AMR(HR) 4.75kbps 14

Bandwidth of a single CS call

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CSVAD: ratio of wanted frames to the total frames. The activation factor relates to such factors as coding/decoding algorithm, environment, VAD, noise reduction algorithm (terminal, TC), and specific session scenario (environmental noise). The value of the activation factor ranges from 0.5 to 1. The default value is 0.5.

8: Each byte has eight bits. 50: one speech frame per 20 ms on the Um interface. Thus, 50 speech frames

are transmitted each second. 1024: 1024 bits equal 1K bits.

Average Abis interface bandwidth on each TCH The result can be obtained by multiplying the data in the corresponding two

columns, and then calculating the sum of all the values. When the ratio of AMR of each voice version is inaccessible, if the simplified

configuration is used, only the ratio of FR channels and HR channels can be used for calculation.


The following data marked yellow is used as examples.

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The result can be obtained by multiplying the data in the corresponding two columns, and then calculating the sum of all the values

When the ratio of AMR of each voice version is inaccessible, if the simplified configuration is used, only the ratio of FR channels and HR channels can be used for calculation.


Codec Ratio IP over FE/GE Frame Len(bit)

IP over FE/GE Tput per unit(kbps)

FR 70% 824 20.1 HR 30% 680 2x16.6 EFR 0% 808 19.7 AMR 0% 824 20.1 AMR 0% 784 19.1 AMR 0% 736 18.0 AMR 0% 728 17.8 AMR 0% 712 17.4 AMR 0% 696 17.0 AMR 0% 680 16.6 AMR 0% 672 16.4 AMR(HR) 0% 736 2x18.0 AMR(HR) 0% 728 2x17.8 AMR(HR) 0% 712 2x17.4 AMR(HR) 0% 696 2x17.0 AMR(HR) 0% 680 2x16.6 AMR(HR) 0% 672 2x16.4

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The size of a single IP framebit

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The size of an RLC/MAC data block varies with coding schemes. A TRAU inband control signaling message consists of eight bytes. TRAU frame header: encapsulates the PTRAU frame. It consists of four bytes. Abis IP over FEGE frame header = 8 x (8 + 20 + 38). It in turn covers the UDP

frame header, IP frame header, and MAC frame header. Bandwidth of a single PS callkbps

50: 50 packet frames per second; 1024: 1,024 bits, equal to 1 kbit/s. PSUsage parameter the PDCH usage, which is an advanced input parameter.

Total Abis interface bandwidth required by PDCHsMbps Abis IP over FEGE Equivalent PDCH number for PS = TRXNoIPFEGE *

CHPerTRX * MaxPDCHRatio

the size of RLC/MAC data blocks in different coding schemes

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Code

Scheme

Service Bit Rate in

RLC/MAC layer (kbps)

Payload in RLC/MAC layer

(bytes)

CS1 9.05 20

CS2 13.4 30

CS3 15.6 36

CS4 21.4 50

MCS1 8.8 22

MCS2 11.2 28

MCS3 14.8 37

MCS4 17.6 44

MCS5 22.4 56

MCS6 29.6 74

MCS7 44.8 112

MCS8 54.4 136

MCS9 59.2 148


MCS9 59.2 148

The following data marked yellow is used as examples.

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Code Scheme Ratio IP over FE/GE Frame Len(bit)

IP over FE/GE Tput per unit(kbps)

CS1 0% 784 38.3 CS2 0% 864 42.2 CS3 0% 912 44.5 CS4 0% 1024 50.0 MCS1 0% 800 39.1 MCS2 0% 848 41.4 MCS3 0% 920 44.9 MCS4 0% 976 47.7 MCS5 0% 1072 52.3 MCS6 100% 1216 59.4 MCS7 0% 1520 74.2 MCS8 0% 1712 83.6 MCS9 0% 1808 88.3

SiteNoIPFEGE and TRXNoIPFEGE are input parameters for BSC and network configuration.

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configuration.


FEGEUsage is an advanced input parameter. The available bandwidth of one GE is: 100 x 1024 x FEGEUsage.

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100 x 1024 x FEGEUsage.

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IP bandwidth needed by a S5/5/5 site

Bandwidth of CS Services =TCH Channel number * Bandwidth of a single CS call =3*(5*8-1-3-10)*20.1=1567.8kbps

1 BCCH,3 SDCCH and 10 PDCH per cell Bandwidth of PS Services =PDCH Channel number * Bandwidth of a single

PS call =3*10*59.4=1782kbps Bandwidth of the LAPD link =OML link bandwidth + RSL link bandwidth

=64+15*16=304kbps Total bandwidth of Abis over IP=Bandwidth of CS Services + Bandwidth of

PS Services + Bandwidth of the LAPD link /FEGEUsage=(1782+1567.8+304)/70%=5142.6 kbps

On the A interface, the signaling plane uses the M3UA/SCTP/IP protocol stack to carry signaling, and the user plane uses the RTP/UDP/IP protocol stack to carry

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carry signaling, and the user plane uses the RTP/UDP/IP protocol stack to carry speech signals

Size of a single IP speech framebit

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TRAU frame: indicates the voice payload consisting of voice and Cbit. The value varies with coding schemes.

A IP over FEGE frame header = 8 x (12 + 8 + 20 + 38), which includes the length of RTP, UDP, IP, or MAC frame header.

Bandwidth occupied by a callkbps 50: 50 voice frames per second. 1024: 1,024 bits, equal to 1 Kbits. CSVAD indicates the voice activation factor, which is an advanced input

parameter. Bandwidth occupied by the user planeMbps

The value of MaxACICPerBSC is obtained through the calculation of the overall capacity of the BSC.

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In A IP over FEGE mode, the SS7 link resources occupied by the equivalent CICs of each A interface in busy hour are supposed to be 0.9 kbit/s.

The value of MaxACICPerBSC is obtained through the calculation of the overall capacity of the BSC.

In Gb over IP, the physical layer uses the FE/GE transmission , the sub NS layer of the NS protocol complies with the IP protocol, and the upper layer of the NS protocol

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the NS protocol complies with the IP protocol, and the upper layer of the NS protocol complies with the BSSGP protocol

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GbUtiRatio indicates the average ratio of the valid data to the total bandwidth in Gb over IP mode. The value is 0.7 by default, which can be adjusted and construed as GbUtiRatio = PayloadLenGb/(PayloadLenGb + 124)

The value of GbTputPerBSC is obtained through the calculation of the overall capacity of the BSC.

1% indicates the average retransmission ratio of Gb interface packets. PayloadLenGb is an advanced parameter. 124 indicates the length of a packet header when the Gb interface works in the

IP transmission mode. GbIPUsage is an advanced parameter, Can be 0 to 1, and Huaweis default

value is 1, if Operator want more resource , Opeartor can caculated by this formula.

P-73

Gb over IP Transmission Usage: 70%The ratio of effective transmission over the Gb interface to the actual physical transmission. Factors such as the retransmission

Gb interface to the actual physical transmission. Factors such as the retransmission rate, peak-to-average burst flow ratio, and signaling overhead rate should be considered in the transmission usage)

Gb Configuration Calculation (IP FE)

Gb Configuration Calculation (IP FE)Data Throughput Demand at the application Layer of the PS Subscriber (kbit/s) 300000*300/1024=87891

IP Bearer Rate per GFPUG (Mbit/s) 128*0.7*0.2/0.2+0.124=55.3IP transmission rate supported by each FE port (Mbit/s) 100*0.7*0.2/0.2+0.124=43.2Rounded number of FE ports that need to be configured on the active GFPUG 87891/(43.2*1024)=1.98Rounded number of active/standby GFPUGs that need to be configured 2*87891/(55.3*1024)=3.12

Course Name P-74


Course Name P-75


Course Name P-76


Course Name P-77


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Course Name P-79


The Dimensioning of interface board please refer to the chapter of TDM and IP transmission dimensioning

P-80

transmission dimensioning

The Dimensioning of interface board please refer to the chapter of TDM and IP transmission dimensioning

Course Name P-81

transmission dimensioning


Course Name P-82


The function items can be controlled by configuration or by host according to the verification and control methods of the system.

P-83

verification and control methods of the system. Controlled by configuration: During system configuration in online or offline

mode, the system compares the effective configuration data with the data authorized by the License. If the data is not authorized by the License, or the configuration data exceeds the data volume authorized by License, or the data does not match the License, the system displays an error message, and the configuration data cannot take effect. The operator must modify the configuration data so that the configuration data takes effect until the data matches the data authorized by License.

Controlled by host: During the actual running of the system, the quantity of some resources in the system is calculated dynamically in real time, the function enabling condition is controlled, and the quantity and enabling condition are compared with those authorized by the License. If the quantity and function enabling condition exceed the authorized range of the License, the system disables the function for the resources that exceed the authorized range of the License.

Function

P-84

Use this command to query the license usage of a specified operator of the NE.

Note In current mode, the allocated and used value of license item about UMTS

primary and secondary Cn Operator and GSM primary Cn Operator will be displayed.

Course Name P-85


Course Name P-86


Course Name P-87


BSC6900 GSM V900R012 Dimensioning

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Transcript of BSC6900 GSM V900R012 Dimensioning