A Single Carrier Iterative Equalization Receiver for Joint Channel Estimation in Time-Varying Channels

A single carrier iterative equalization receiver with joint channel estimation is proposed to solve the time-varying and multipath delay problems in broadband wireless communication channels. Firstly, according to the possibility of signal diversity brought by multipath delay, feedback filter banks are designed to eliminate the inter symbol interference among different delay signals as much as possible. Then, a feedforward filter is designed to combine the multipath components after interference elimination, so as to obtain diversity gain. Finally, according to the pilot information and the soft information output by the iterative equalization module, the channel is iteratively estimated by using the complex exponential basis extension model. Simulation results and a comparison with the existing iterative equalization method for joint channel estimation under fast time-varying channel show that the performance of the proposed method improves by 1 dB and is about 1 dB away from the matched filter bound after three times of iterations in the case of large delay spread and small Doppler frequency offset when the bit error rate is 10-5. When the bit error rate is 10-5 in the case of small delay spread and large Doppler frequency offset, the performance of the proposed method improves by about 2 dB and is about 0.8 dB away from the matched filter bound after three times of iterations. © 2021, Editorial Office of Journal of Xi'an Jiaotong University. All right reserved.