Approximations to joint-ML and ML symbol-channel estimators in MUD CDMA
نویسندگان
چکیده
In this contribution will we conceptually derive two symbolchannel estimators, the joint-ML and the ML, both having exponential complexity. Pragmatically we derive three approximations with polynomial complexity, one to the joint-ML: the pseudo-joint-ML; two to the ML: the naive-ML and the linear-response-ML. We asses the resulting average bit error rates empirically. Performance gains of several dBs are observed from using the ML based approximations compared to the jointML. Keywords—CDMA, Multiuser Detection, Blind channel estimation
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