A turbo receiver combined with CFO compensation in frequency-domain for OFDMA uplink

摘要

Turbo receivers have been widely studied and used in the field of iterative signal processing. In this paper, a novel turbo receiver combined with multiuser carrier frequency offset (CFO) compensation in frequency-domain is proposed for orthogonal frequency division multiple access (OFDMA) uplink. Based on the principle of frequency-domain turbo equalization, the proposed turbo receiver jointly performs soft interference cancellation (SIC)-based CFO compensation in frequency-domain, minimum mean square error (MMSE)-based frequency-domain equalization and maximum a posteriori (MAP)-based decoding in an iterative fashion. Analysis and simulation results show that the proposed turbo receiver which exploits soft-decision feedback derived from decoders provides better frequency synchronization and bit error rate (BER) performance than the non-iterative receivers which employ conventional equalization and decoding without decision feedback. Moreover, the proposed turbo receiver achieves better BER performance, faster convergence rate and lower complexity than some existing turbo receivers for OFDMA uplink.