A Simple Soft-In Soft-Out Equalization for Highly Mobile OFDM Systems with Block Markov Superposition Transmission

摘要

In this paper, we propose a simple and efficient soft- in soft-out (SISO) equalization for block Markov superposition transmission (BMST) in the coded OFDM system (called BMST-OFDM) over high-mobility wireless communication channels. In the BMST-OFDM system, the proposed SISO equalizer can exchange soft messages with the soft demapper and the BMST decoder in an iterative fashion. Simulation results show that 1) compared with some existing advanced equalization algorithms, our proposed algorithm performs better in the BMST-OFDM system, 2) our proposed equalization algorithm has lower computational complexity than the conventional algorithms since it avoids both constructing a huge state space trellis and calculating the inversion of a matrix, and 3) the proposed scheme is robust to various velocities, and its performance matches well with the lower bound in the high signal-to-noise ratio (SNR) region.