본문 바로가기
KERD
논문KCI 등재

고속 레일레이 페이딩 채널에서 STBC-OFDM의 간섭 분석 및 보상

The Analysis and Compensation of Interferences for STBC-OFDM in a Fast Rayleigh Fading Channel

3

조회

0

다운로드

0

인용

0

참고문헌

키워드

초록

MRC(Maximal Ratio Combining) 기반의 복호 방식을 사용하는 STBC-OFDM(Space-Time Block Coded Orthogonal Frequency-Division Multiplexing)에서는 시변 채널에 의해 채널간 간섭(ICI: Inter-Channel Interference)과 함께 자기 채널 간섭(SCI: Self-Channel Interference)이 발생한다. 본 논문에서는 STBC-OFDM 에서 발생되는 SCI의 특성을 분석하고, SCI의 전력을 채널의 시간 영역 자기 상관 함수를 이용하여 유도한다. SCI의 전력이 채널의 시간 변화율에 비례하며, 그 크기가 ICI의 전력보다 크게 나타남을 보인다. 고속 시변 채널에서 STBC-OFDM의 성능을 향상시키기 위해 수신단에서의 SCI 발생을 근원적으로 방지할 수 있는 간단한 사전제거 (pre-canceling) 기법을 제안한다. 또한 수신단에서 최대비율 기준에 의해 결합된 OFDM 심볼의 SCI 영향을 SCI 구 조를 이용하여 보상할 수 있는 사후제거(post-canceling) 기법을 제안한다. 제안된 보상 기법을 두 개의 송신 안테나 와 두 개의 수신 안테나를 사용하는 STBC-OFDM에 적용할 경우 0.0889의 채널 변화율과 2bps/Hz의 대역폭 효율 에서 10-4 이하의 BER을 얻을 수 있다.

Abstract

Self-channel interference (SCI) as well as inter-channel interference (ICI) is occurred by time-varying channels in space-time block coded orthogonal frequency-division multiplexing (STBC-OFDM) using conventional maximal ratio combining (MRC) based decoding scheme. In this paper, we analyze the characteristic of the SCI and derive SCI power by using a time-domain correlation function of Rayleigh fading channel. We show that the SCI power is proportional to rate of channel variation and higher than the ICI. A simple pre-canceling technique is proposed to prevent the SCI and is shown to improve the performance of the STBC-OFDM. A post-canceling technique that can compensate the effect of the SCI after the MRC is also proposed by considering the structure of the SCI. The proposed techniques can provide a bit error rate (BER) lower than 10-4 for the STBC-OFDM using two transmit and two receive antennas, under the rate of channel variation of 0.0889 and a bandwidth efficiency of 2bit/s/Hz.

참고문헌 (28)

  1. "''Analysis and simulation of a digitalmobile channel using orthogonal frequency-divisionmultiplexing", 33, pp.665~675
  2. "''Multicarrier modulation for datatransmission", 28, pp.5~14
  3. "Beyond 3G: vision,requirements, and enabling technologies", (3), pp.120~124
  4. "A simple transmit diversity techniquefor wireless communications", 16(8), pp.1451~1458
  5. "Space -time block codes from orthogonal designs", 45(5), pp.1456~1467
  6. "IEEE Standard for Local and Metropolitan AreaNetworks -Part 16: Air Interface for Fixed BroadbandWireless Access Systems-Amendment 2: MediumAccess Control Modifications and Additional PhysicalLayer Specifications for 2-11 GHz"
  7. "Improvingperformance of coherent coded OFDM systems usingspace time transmit diversity", 37(7), pp.457~458
  8. "A space -time block-coded OFDM scheme for unknown frequency -selective fading channels", 5(10), pp.393~395
  9. "Transmit antennae space-time blockcoding for generalized OFDM in the presenceof unknown multipath", 19(7), pp.1352~1364
  10. "Differential space-time coding for frequency -selective channels", 6(6), pp.253~255
  11. "Interchannel interferenceanalysis of OFDM in a mobile environment", pp.820~824
  12. "''The effects of Dopplerspreads in OFDM(A) mobile radio systems", pp.329~333
  13. "Effects of time selectivemultipath fading on OFDM systems for broadbandapplications", 3(12), pp.332~334
  14. "Time-variant distortionsin OFDM", 4(10), pp.312~314
  15. "An equalization technique for OFDM systems in time-variant multipath channels", 47(1), pp.27~32
  16. "Intercarrier interferself-cancellation scheme for OFDM mobile communication systems", 49(7), pp.1185~1191
  17. "Second-order channel parameter estimation assisted cancellation of channel variation-induced inter-subcarrier interference in OFDMsystems", pp.1~5
  18. "Polynomial cancellation coding of OFDM to reduce intercarrier interference due to Doppler spread", pp.2771~2776
  19. "Intercarrier interference in MIMO OFDM", 50(10), pp.2451~2464
  20. "Bounds on the interchannel interference of OFDM in time-varying impairments", 49(3), pp.401~404
  21. "Clustered OFDM withchannel estimation for high rate wireless data", 49(12), pp.2071~2076
  22. "A space-frequencytransmitter diversity technique for OFDM systems", pp.1473~1477
  23. "A practical space-frequency block coded OFDMscheme for fast fading broadband channels", pp.212~216
  24. "Digital Communications", 14(2), pp.2001~ (2004), Prentice Hall
  25. "Wireless OFDM Systems: How to make them work?" (2002), Kluwer AcademicPublishers
  26. "Analysis and optimization of the performance of OFDM on frequency -selective time-selective fading channels", 47(12), pp.1811~1819
  27. "Channelestimation for OFDM systems with transmitter diversityin mobile wireless channels", 17, pp.461~471
  28. "Two-dimensional MMSE channel estimation for OFDMsystems with transmitter diversity", pp.1682~1685

관련 논문AI추천

이 간행물의 다른 논문 (14건)