JOINT CHANNEL ESTIMATION AND CCI CANCELLATION FOR STBC-OFDM SYSTEM IN TIME VARYING MULTIPATH FADING CHANNEL
Keywords:OFDM, STBC, CCI, Channel Estimation
The performance analysis of Alamouti coded SpaceÂ Time Block Code (STBC) based Orthogonal Frequency DivisionÂ Multiplexing (OFDM) is generally analyzed by assuming that theÂ channel remain constant over two consecutive OFDM symbolÂ blocks. However, in fast fading channel this assumption does notÂ hold good and causes Co-channel Interference (CCI) due to channelÂ variation during two adjacent ODM symbols. To cancel the CCIÂ effects, different detection methods have been proposed inÂ literature. Some of them are namely, Successive InterferenceÂ Cancellation (SIC), Zero Forcing (ZF), Decision Feedback (DF)Â and Maximum Likelihood (ML). These detection methods areÂ performed by assuming that the complete channel knowledge isÂ known at the receiver side. But, in practical scenario, the channel isÂ unknown to the receiver. This paper presents a simple joint channelÂ estimation and CCI cancellation in STBC OFDM system in fastÂ fading channel. A different pilot location scheme is proposed toÂ estimate the channel. SIC, ZF, DF and ML detection schemes areÂ followed by channel estimation. The performance of differentÂ detection methods with estimated and perfect channelÂ information are compared on the basis of symbol error
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