Parallel Interference Cancellation Based Signal Detection for OFDM/OQAM Systems

Because of the usage of practical windowed pulse shaping filter and limitation of real field orthogonality of OFDM with Offset QAM (OFDM/OQAM) systems, the zero-forcing equalization as signal detector can not completely remove the Inter-Symbol Interference (ISI) and Inter-Carrier Interference (ICI) introduced by multipath fading channels. The ISI and ICI lead to severe degradation of BER performance of OFDM/OQAM system. Moreover, the imperfect channel estimation by using preamble also results in the further BER performance degradation. In this paper, one Parallel-Interference-Cancellation (PIC) signal detection method based on zero-forcing equalization for OFDM/OQAM systems is proposed by reconstruction of ISI and ICI with aid of initial data detection. And analytical results on residual interference by Zero-Forcing (ZF) and imperfect channel estimator are given. Finally, simulation results demonstrate that OFDM/OQAM system with PIC signal detector can achieve better BER performance by 1 dB to 2 dB while BER equal to 1% than conventional signal detector.