Performance Analysis of Orthogonal Chirp Division Multiplexing System with Zero-Forcing Receiver over Multi-Path Fading Channels

With multi-path propagation, the transmitted signal experiences varying degrees of fading, which greatly impacts the current 4G/5G communication system based on orthogonal frequency division multiplexing (OFDM) modulation. In recent years, the orthogonal chirp division multiplexing (OCDM) modulation has emerged as an attractive alternative to the OFDM due to its increased resistance to fading channel impairments. Although numerous studies have been done on OCDM communication systems recently, a comprehensive statistical analysis of the post-detection signal-to-noise ratio (SNR) with zero-forcing (ZF) receiver is still lacking. In this paper, we investigate the statistical properties of the received symbol SNR in a multi-path propagation environment for a point-to-point OCDM communication system. We first derive the SNR expression for the demodulated symbol using ZF receiver. Then we analyze the distribution of the SNR, demonstrating that it depends on the joint distribution of the eigenvalues of channel matrix. Following this, we provide a comprehensive derivation of the probability distribution function (PDF) of the SNR for both single-path and two-ray propagation environment. The so-derived PDFs are utilized to provide key insights into the OCDM system in terms of the bit error rate. Finally, the accuracy of our analytical results have been validated with Monte Carlo simulations.