Adaptive PSP-MLSE receiver for GSM/EDGE system in fast multipath fading channels

Abstract

An adaptive MLSE receiver based on per-survivor processing (PSP-MLSE) for the GSM/EDGE system with 8PSK modulation is presented. The initial channel impulse response is estimated by the LS algorithm with a training midamble sequence. The PSP-MLSE is in conjunction with the LMS algorithm to track the fast time-varying channel. Based on the EDGE burst structure, the second part of the data stream is tracked forwards while the first part is tracked backwards in order to improve the performance in rapidly changing channels. Computer simulations indicate that the PSP-MLSE is clearly superior to the conventional adaptive MLSE (CA-MLSE), especially, at high velocities. Moreover, the loss due to the estimation error is also presented by measuring the ideal system performance. Furthermore, the termination effect of the Viterbi algorithm is also discussed.