RAKE Combining Receiver in Frequency Selective Fading Channels

Aiming at the multipath diversity reception in non-spectrum-spreading system,a RAKE combining receiver is presented in this paper.The estimate of the transmitted data is obtained by the IIR(infinite impulse response) equalizer with decision feedback(DF) structure,and each multipath signal can be resumed by this initial solution.Then the multipath elements in the received signal are obtained,and the components are combined together using maximal ratio combining(MRC) before the final decision,so RAKE combining receiver is accomplished.The cumulated round off noise phenomenon is eliminated by DF-IIR,however,error propagation exists in the decision directed filter.While the signal-to-noise ratio(SNR) can be increased evidently after MRC,the error propagation problem is depressed dramatically in the combining receiver.Simulations show that the proposed algorithm can achieve the performance advantages effectively.