Variable Range Resampling for Computationally Efficient Doppler Compensation in Underwater Acoustic Communication

In shallow-water acoustic communication, OFDM is used owing to robustness with highly selective frequency fading channels. As for the countermeasure of OFDM sensitivity to Doppler, resampling is known as one of effective approaches as Doppler compensation. Performance degradation occurs under non-uniform Doppler shifts where the Doppler scaling factor is not constant. Our previous work presented parallel resampling with considering Doppler shift dispersion. It improved Doppler resilience, however required exhaustive computation. We study complexity reduction of parallel resampling receiver where the degree of parallelism is dynamically controlled on a frame-by-frame basis, This method can reduce complexity of resampling with keeping the same communication performance.