Analysis of Channel Estimation Algorithms in a RAKE Receiver with MRC

MRC 결합의 레이크 수신기에서 채널 추정 알고리즘의 성능분석

  • 전준수 (전남대학교 정보통신연구소)
  • Published : 2004.08.01

Abstract

In this paper, we analyze channel estimation algorithms in a RAKE receiver with MRC. There are 3 popular channel estimation algorithms, which are WMSA(Weighted Multi-Slot Averaging) algorithm, EGE(Equal Gain Estimation) algorithm, SSE(Symbol-to-Symbol Estimation) algorithm. We analyze asynchronous IMT-2000(3GPP) which employ 3 different channel estimation algorithms by HP-ADS(Advanced Design System) simulation tool. We used lakes fading channel model for the analysis. from simulation results, we could observe that the performance of WMSA algorithm is better than others in low Doppler effect(3Km/h). However, in the case of high Doppler effect(120km1h), the EGE algorithm is more efficient. In this case the simple estimator with EGE algorithm seems to be more useful.

본 논문에서는 MRC(Maximal Ratio Combing) 결합 기법을 사용한 RAKE 수신기에서 채널 추정 알고리즘에 따른 성능을 분석한다. 채널 추정 알고리즘에는 WMSA(Weighted Multi-Slot Averaging), 동일 이득 채널 추정 (Equal Cain Estimation ; ECE), 심볼 단위 채널 추정(Symbol-to-Symbol Estimation ; SSE)의 세 가지가 있는데 상업용 시뮬레이션 틀인 HP사의 ADS를 이용하여 비동기 방식 IMT-2000시스템(3GPP)을 대상으로 성능을 분석한다. 성능 분석을 위해서 본 논문은 Jakes 페이딩 채널 모델을 사용한다. 모의실험 결과를 통하여, 저속 도플러(3Km/h)일 때 WMSA 알고리즘이 다른 알고리즘 성능보다 더 좋음을 알 수 있다. 그러나 고속 도플러(120Km/h)일 때, 간단한 구조를 갖는 ECE 알고리즘이 보다 더 유용함을 알 수 있다.

Keywords

References

  1. H. Holma, A. Toskala, WCDMA for UMTS(Radio Access for Third Generation Mobile Communications), A Wiley-Interscience Publication, 2000
  2. H. Andoh, M. Sawahashi, and F. Adachi, 'Channel Estimation Using Time Multiplexed Pilot Symbols for Coherent Rake Combining For DS-CDMA Mobile Radio,' in Proc. of 8th PIMRC'97, vol.3, pp. 954-958, 1997
  3. Khalid A. Qaraqe, Sonia Roe, 'Channel Estimation Algorithms for Third Generation W-CDMA Communication Systems,' in Proc. of IEEE Veh. Technol. Conf., Rodes, Greece, May 6-9, 2001
  4. Timothy M. Schmidl, Anand G. Dabak, Srinath Hosur, 'The use of Iterative Channel Estimation(ICE) to improve link margin in Wideband CDMA Systems,' in Proc. of IEEE Veh. Technol. Conf., Houston, Texas, vol.2, pp. 1307-1311, May 16-19 1999
  5. 3GPP Technical Specification 25. 212, Multiplexing and channel coding (FDD)
  6. 3GPP Technical Specification 25. 214, Physical layer procedures (FDD)
  7. John. G. Proakis, Digital Communication, McGraw-Hill, 1995
  8. K. Kettunen, 'Enhanced maximal ratiocombining scheme for RAKE receivers in WCDMA mobile terminals,' Electronics letters, vol. 37, no. 8, pp. 522-524, April 2001 https://doi.org/10.1049/el:20010364
  9. P. Dent, G. E Bottomely and T.Ccroft, 'Jakes fading model revisited,' Electronics letters 24th, vol. 29, no. 13, pp. 1162-1163, June 1993 https://doi.org/10.1049/el:19930777
  10. William C. Jakes,. Microwave Mobile Communications, A Wiley-Interscience Publication, 1974