Teletalk 3G Coverage While Migrating Into 3G

In this case study it is suggested to introduce teletalk 3g coverage and then expand it with demand from the customer side and availability of fund from the government. As a pilot project, in this study a sample calculation has been made considering only the Gulshan and Banani area being migrated to 3G. According to TRX calculation, 1 TRX = combined BCCH and SDCH that makes 7 TCH channels. 2 TRX = 1 BCCH and 1 SDCH that makes 14 traffic channels (TCH). 3 TRX = 1 BCCH and 2 SDCH that makes 21 traffic channels (TCH).  Erlang value has been taken from Erlang Table according to GOS = 0.020. Table below shows existing BSS configuration

This table of Teletalk network shows existing BTS configuration.

BTS NameConfiguration
(900+1800)
GSM+ WCDMATrafficChannelsTrafficErlang /SectorTotalErlang
Gulshan 2/ S Ho.2/2/2+1/1/114*3+7*38.20*3+2.93*324.6E+8.79E33.39E
Gulshan BTTB2/2/2+2/2/214*3+14*38.20*3+8.20*324.6E+24.6E49.2E
Gulshan Rd 352/2/2+1/1/114*3+7*38.20*3+2.93*324.6E+8.79E33.39E
Gulshan Road 552/2/214*38.20*324.6E24.6E
Gulshan Road 1071/1/1+3/3/37*3+21*32.93*3+14.03*38.79E+42.09E50.88E
Gulshan Rd 1162/2/2+1/1/114*3+7*38.20*3+2.93*324.6E+8.79E33.39E
Kakoli2/2/2+2/2/214*3+14*38.20*3+8.20*324.6E+24.6E49.2E
Teletalk (Banani)2/2/214*38.20*324.6E24.6E
Banani Rd 52/2/2+1/1/114*3+7*38.20*3+2.93*324.6E+8.79E33.39E
Banani Rd 182/2/2+1/1/114*3+7*38.20*3+2.93*324.6E+8.79E33.39E
Banani Rd 19/A2/2/2+2/2/214*3+14*38.20*3+8.20*324.6E+24.6E49.2E
DOHS Baridhara2/2/214*38.20*324.6E24.6E
Baridhara Rd 2D1/1/17*32.93*38.79E8.79E
Baridhara Rd 132/2/214*38.20*324.6E24.6E
Karail2/2/214*38.20*324.6E24.6E
15 BTS126 TRX882 Traffic Channels  497.22E

The following parameter can be considered –

  • GoS = 0.020
  • No of BTS = 15
  • Cell = 72
  • Total Erlang = 497.22E
  • TRX = 126
  • Traffic Channels = 882
  • Total subscriber that can be catered considering 20 mErlang/subscriber during Busy Hour = 497.22 / 0.020 = 24861 subscribers

Mapping GSM Capacity and Teletalk 3G Coverage:

The planned network has been designed with both GSM and WCDMA technology working simultaneously. GSM band is applicable for GSM BTS and WCDMA band is applicable for 3G NodeB. Existing GSM supported BTS will remain same. Grade of service (GOS) of 0.020 for GSM and 0.015 for 3G has been calculated. After analysis it is found that 20 BTS will be required instead of 15 BTS [6]. In 3G there are 36 channels per cell and 108 channels per site has been considered. Below BTS/ NodeB configuration has been shown both for GSM and WCDMA system that is generic configuration. The configuration may change according to drive test and subscriber density. The coverage of umts sim or wcdma sim is different than gsm sim.

Table: – Teletalk Migrated BTS configuration.

BTS+ NodeB AreaTRXConfiguration
900M+1800+ WCDMA
TrafficChannels900M+1800M+ WCDMAErlang900M+1800M+ WCDMAErlang900M+1800M+ WCDMA
Gulshan1/1/1 +1/1/1 +1/1/17*3+7*3  +36*32.93*3+2.93*3+ 26.43*38.79E +8.79E + 79.29E
Gulshan2/2/2+ 1/1/1 +1/1/114*3+7*3+36*38.20*3+ 2.93*3+26.43*324.6E +8.79E + 79.29E
Gulshan1/1/1 +1/1/1 +1/1/17*3+7*3  +36*32.93*3+2.93*3+ 26.43*38.79E + 8.79E +79.29E
Gulshan2/2/2 +1/1/1 +1/1/114*3+7*3+36*38.20*3+ 2.93*3+26.43*324.6E +8.79E + 79.29E
Gulshan1/1/1 +1/1/1 +1/1/17*3+7*3  +36*32.93*3+ 2.93*3+26.43*38.79E +8.79E + 79.29E
Gulshan2/2/2 +1/1/1 +1/1/114*3+7*3+36*38.20*3+2.93*3+ 26.43*324.6E + 8.79E +79.29E
Gulshan1/1/1 +1/1/1 +1/1/17*3+7*3  +36*32.93*3+2.93*3+ 26.43*38.79E +8.79E  +79.29E
Gulshan1/1/1 +1/1/1 +1/1/17*3+7*3  +36*32.93*3+ 2.93*3+26.43*38.79E  +8.79E +79.29E
Bonani2/2/2 +1/1/1 +1/1/114*3+7*3+36*38.20*3+ 2.93*3+26.43*324.6E + 8.79E +79.29E
Bonani1/1/1 +1/1/1 +1/1/17*3+7*3  +36*32.93*3 +2.93*3+26.43*38.79E +8.79E + 79.29E
Bonani2/2/2 +1/1/1 +1/1/114*3+7*3 +36*38.20*3 +2.93*3+26.43*324.6E +8.79E + 79.29E
Bonani1/1/1 +1/1/1 +1/1/17*3+7*3   +36*32.93*3 +2.93*3+26.43*38.79E +8.79E + 79.29E
Bonani2/2/2 +1/1/1 +1/1/114*3+7*3 +36*38.20*3 +2.93*3+26.43*324.6E +8.79E + 79.29E
Bonani1/1/1 +1/1/1 +1/1/17*3+7*3  +36*32.93*3 +2.93*3+26.43*38.79E +8.79E +79.29E
Bonani1/1/1            +1/1/17*3         +36*32.93*3              +26.43*38.79E              + 79.29E
Baridhara2/2/2            +1/1/114*3       +36*38.20*3              +26.43*324.6E              + 79.29E
Baridhara1/1/1            +1/1/17*3         +36*32.93*3              +26.43*38.79E              + 79.29E
Baridhara1/1/1            +1/1/17*3         +36*32.93*3              +26.43*38.79E              + 79.29E
Baridhara1/1/1            +1/1/17*3         +36*32.93*3              +26.43*38.79E              + 79.29E
Baridhara1/1/1            +1/1/17*3         +36*32.93*3              +26.43*38.79E              + 79.29E
20 Site  102+60 Cell123+60 TRX 861+2160 Channels Traffic 409.5 E      +1585.8 E          = 1995.3E

E = Erlang, M = MHz

The following parameter can be considered –

  • GOS = 0.020 for GSM and 0.015 for 3G
  • Total TRX  GSM  123 + WCDMA 60  = 183 TRX
  • Total BTS = GSM BTS 20 + 3G NodeB 20 = 40
  • Total Cell = GSM 102+ 3G 60 = 162
  • Total Erlang = 409.5+1585.8 E = 1995.3E
  • Subscriber at a time in GSM = 409.5 / 0.020 = 20475 subscribers.
  • Subscriber at a time in 3G 1585.8/0.015 = 105720 subscribers
  • Total subscribers in dual network 20475 + 105720 = 126195 subscribers

UMTS Router:

This is new technology of cellular mobile system. UMTS router is a special router for its internal networking system.

UMTS Router
UMTS Router

One UMTS router can cover a lot of host. WCDMA sim and UMTS SIM is mandatory for the router system.

Teletalk Migration from GSM to 3G Part Ten

Teletalk Migration from GSM to 3G Part Nine

Teletalk Migration from GSM to 3G Part Eight

Teletalk Migration from GSM to 3G Part Seven

Teletalk Migration from GSM to 3G Part Six

Teletalk Migration from GSM to 3G Part Five

Teletalk Migration from GSM to 3G Part Four

Teletalk Migration from GSM to 3G Part Two

Teletalk Migration from GSM to 3G Part One

Please contact me for part Four to Ten.

Student
Name : Md. Khondakar Mashiur Rahman
University of Information Technology and Science
ID : 060561
Program : M.Sc. in Telecommunication
Cell Number: +880 17 92 52 53 54