Interference cancellation aided channel estimation for OFDM/OQAM system

Abstract

Orthogonal frequency division multiplexing offset-QAM (OFDM/OQAM) is a promising multicarrier transmission technique for its merits such as operating without cyclic prefix (CP) and flexibility of introducing well time-frequency localized pulse shapes. However, under dispersive channel condition, the intrinsic inter-symbol and inter-carrier interference arises in OFDM/OQAM system. Especially, the surrounding data symbols will cause interferences to the pilot symbols, leading to channel estimation error and degradation of system performance. In this paper, an efficient pilot structure and a channel estimation method are proposed for OFDM/OQAM system. The basic principal is to rebuild the transmitted symbols around the considered pilot position through pre-decision, then calculate and cancel the interference from the received signal. Analysis and simulation results show that the proposed scheme outperforms conventional ones with respect to both channel estimation accuracy and bit error rate (BER) performance while with less pilot consumption.