Max-SINR Based Timing Synchronization Scheme in Hexagonal Multicarrier Transmission

Abstract

In this paper, the maximizing Signal-to-Interference-plus-Noise Ratio (Max-SINR) criterion is applied in Hexagonal Multicarrier Transmission (HMT) system for timing synchronization. An iterative approach for Max-SINR timing over doubly dispersive (DD) channel with exponential power delay profile and U-shape Doppler spectrum is proposed. Theoretical analysis shows that there is an allowable SINR gap between the mean delay of DD channel and the optimal timing point. Meanwhile, a low complexity suboptimal timing approach based on instantaneous channel frequency response is proposed. Theoretical analysis and simulation results show that Max-SINR timing scheme outperforms traditional timing method about 2–15 dB in SINR and the suboptimal timing algorithm achieves a smaller Mean Square Error than 10−4 over DD channels. In addition, the Iterative Projection Sequence Detection (IPSD) receiver is proposed and the Match Filter Low Bound (MFLB) in HMT system is given. Simulation results show that the Bit Error Rate (BER) of the proposed IPSD approach based on iterative Max-SINR timing approximates to the MFLB and outperforms traditional timing scheme about 3dB at BER = 10−3.