Characterization of GFDM signal with timing offset, CFO, nonlinearity, and PN

In this paper, we study the joint effects of timing offset (TO), carrier frequency offset (CFO), phase noise (PN), and nonlinear power amplifier distortion on a generalized frequency division multiplexing (GFDM) system. Classifying the TO into four cases based on the direction of offset, our work analyzes the signal-to-interference ratio (SIR) for each of the four cases at the GFDM receiver in the presence of synchronization errors, PN, and nonlinear power amplifier. Then, we conduct simulations to compare the performance of GFDM systems under these impairments with that of orthogonal frequency division multiplexing (OFDM) systems, considering both matched filter and zero-forcing. The results show that GFDM systems are more robust against TO and PN while they are more sensitive to CFO and nonlinear distortion compared to OFDM systems. More specifically, it is shown that employing GFDM improves the system SIR compared to OFDM by up to 3 dB and 1.5 dB under TO and PN distortions, respectively.