On the robustness of oversampled filter bank multi carrier systems against frequency offset

In this paper, we study the effect of oversampling in a perfect reconstruction (PR) filter bank multi carrier (FBMC) system recently proposed by the authors. Particularly, we investigate the performance of this system in the presence of carrier frequency offset (CFO). We show that the CFO introduces interference components in the receiver. By exploiting the statistical properties of the received subband signals, the average of the signal-to-interference ratio (SIR) is derived to exhibit the tradeoff between performance and efficiency. Furthermore, bit-error-rate (BER) comparisons of FBMC systems with different oversampling ratios over frequency-selective and additive white Gaussian noise (AWGN) channels in the presence of CFO are presented. These results confirm that oversampling increases robustness of the system against CFO.