전파음영 채널 환경에서 소프트 핸드오프 기법이 CDMA 셀룰러 시스템의 셀 커버리지에 미치는 영향

Effect of Soft Handoff Technique on CDMA Cell Coverage in a Lognormally Shadowed Channel

  • 오현규 (충북대학교 정보통신공학과) ;
  • 김항래 (충북대학교 정보통신공학과) ;
  • 김남 (충북대학교 정보통신공학과)
  • Oh, Hyon-Kyu (Dept.of Computer and Communication Engineering, Chungbuk National University) ;
  • Kim, Hang-Rae (Dept.of Computer and Communication Engineering, Chungbuk National University) ;
  • Kim, Nam (Dept.of Computer and Communication Engineering, Chungbuk National University)
  • 발행 : 2001.10.01

초록

본 논문에서는 로그노말(log-normal) 분포된 전파음영(shadowing) 채널 환경에서 소프트 핸드오프 기법이 CDMA 셀룰러 시스템의 셀 커버리지에 미치는 영향을 Hata 전파 모델을 사용하여 분석한다. 또한 전파음영에 따른 하드 핸드오프 마진과 소프트 랜드오프 마진을 계산하여 셀 커버리지 증가율을 산출한다. 전파음영 채널환경에서 차단 확률(outage probability)이 0.02이고, 수신신호 전력의 표준편차가 2.5 dB이면 셀 경계 부근에 위치한 이동국의 송신 전력은 5.13 dB의 하드 핸드오프 마진과 3.68 dB의 소프트 핸드오프 마진만큼 증가한다. 따라서 소프트 핸드오프 기법을 사용함으로서 얻을 수 있는 셀 커버리지 증가율은 1.39가 된다. ( $E_{b/}$ $N_{0}$)$_{req}$ 값을 7 dB로 가정하면, 도심지역에서 소프트 핸드오프 기법을 사용하는 CDMA 셀룰러 시스템의 셀 커버리지는 주파수가 850 MHz 일 때 3.33 km이고, 1900 MHz일 때 1.36 km가 된다는 것을 알 수 있다. 또한 소프트 핸드오프 기법을 사용한 CDMA 셀룰러 시스템에서 기지국이 서비스 할 수 있는 정확한 셀 커버리지를 제공한다.다.다.다.

In this paper, the effect of soft handoff technique on CDMA cell coverage is analyzed in a lognormally shadowed channel, which uses the Hata propagation model, Also, the rate of increase for the cell coverage is analyzed by calculating the hard and soft handoff margin. When the outage probability is 0.02 and the standard deviation of the received signal is 2.5 dB in a lognormally shadowed channel, the transmit power of the mobile station which is located in the cell boundary is increased by the hard handoff margin of 5.13 dB and by the soft handoff margin of 3.68 dB, respectively. So, the rate of increase for the cell coverage is 1.39 in case of using the soft handoff technique. It is shown that if the (E$\_$b//N$\_$0/)$\_$req/ value is 7 dB, the cell coverage of the CDMA cellular system with soft handoff technique in city area is 3.33 km in case of the 850 MHz frequency and 1.36 km in case of the 1900 MHz frequency. Also, the accurate cell coverage with soft handoff technique is supported that could be serviced by the base-station in CDMA cellular system.

키워드

참고문헌

  1. IEEE Transactions on Vehicular Technology v.49 no.5 Behavior and performance of power controlled IS-95 reverse- link under soft handoff F. Ling;R. Love;M. M.Wang;T. Brown;P. Fleming;Hua Xu
  2. IEEE Transactions on Vehicular Technology v.48 no.5 The coverage-capacity tradeoff in cellular CDMA systems V. V. Veeravalli;A. Sendonaris
  3. IEEE 44th Vehicular Technology Conference v.2 Analysis of CDMA range extensions due to soft handoff M. Chopra;K. Rohani;J. D. Reed
  4. Microwave Journal v.38 no.7 Trading coverage for capacity in cellular systems: A systems perspective C.Wheatley
  5. IEEE Journal on Selected Areas in Communications v.12 no.8 Soft handoff extends CDMA cell coverage and increase reverse link capacity A. J. Viterbi;A. M. Viterbi;K. S. Gilhousen;E. Zehavi
  6. Mobile Cellular Telecommunications Systems(Second Edition) W. C. Y. Lee
  7. National Bureau of Standards Applied Mathematics Series 55 Handbook of Mathematical Functions M. Abramowitz(ed);I. A. Stegun(ed)
  8. Antennas and Propagation for Wireless Communication Systems S. R. Saunders
  9. IEEE Transactions on Vehicualr Technology v.29 no.3 Empirical formula for propagation loss in land mobile radio services M. Hata
  10. ANSI J-STD-008 Personal Station-Base Station Compatibility Requirements for 1.8 to 2.0 GHz Code Division Multiple Access(CDMA) Personal Communications Systems
  11. IEEE Transactions on Vehicular Technology v.40 no.2 On the capacity of a celluar CDMA system K. S. Gilhousen;I. M. Jacobs;R. Padovani;A. J. Viterbi;L. A. Weaver;C. A. Wheatley
  12. IEEE Personal Communications v.1 Reverse link performance of IS-95 based cellular systems R. Padovani
  13. IEEE Transactions on Communications v.42 no.2 Other-cell interference in cellular power-controlled CDMA A. J. Viterbi;A. M. Viterbi
  14. Digital Communications Fundamentals and Applications(Second Ed.) B. Sklar