The influence of ISI on channel estimation and optimized channel estimation in PSK-chirp system

Abstract

Due to the influence of filters and multipath channels, the received signal of the current symbol will be affected by the interference of the previous symbol and the next symbol, the interference will reduce the performance of channel estimation, especially when the SF is relatively low, which will affect the system throughput rate. In this paper, based on BPSK chirp spread spectrum modulation system, we first describe the channel estimation of matched filtering and FFT, and derive the influence of ISI on the channel estimation of the current pilot symbol. Then we proposed the improved channel estimation based on the estimated time delay spread and transmitted signals. Finally, we simulate the MSE performance of channel estimation under different channels and different transmitted signals. The simulation results show that the MSE performance of the improved channel estimation can be improved under different channel when the SF is low, and higher throughput can be obtained.