Study of coexistence for communication signals and radar target detection over fading channels

Abstract

Because of the increasing demands of spectrum resources, the coexistence of radar and communication systems has become an important research topic. Due to the double selective fading channel, the signal undergoes multipath propagation and Doppler frequency shift during transmission, which not only leads to a decrease in signal quality, but also interferes with each other when the radar system and communication system operate in the same frequency, further exacerbating the impact of channel fading.

To address these issues, researchers have proposed various technical means. For example, advanced signal processing techniques such as beamforming, power control, spectrum sensing, and interference management [1] can effectively separate radar signals and communication signals in the time and frequency domain. The application of collaborative communication technology and cognitive radio technology has also provided ideas for the coexistence of radar and communication systems in the spectrum.

The main objective of this project is to use MATLAB simulation to study the coexistence problem of radar and communication signals in double selective fading channels. For convenience, binary communication signals and frequency modulated continuous wave (FMCW) radar are chosen, and the coexistence of the two signals on additive white Gaussian noise (AWGN), Rayleigh fading, and Rician fading channels was mainly discussed. Communication signals use bit-error rate (BER) as the standard to measure signal performance, while radar signals use the accuracy of measuring speed and range as accurate standard to measure radar signals. This project mainly proposes methods to improve the performance of two types of signals from the perspectives of power, coexisting frequency, and degree of interference between signals, and draws corresponding conclusions.