Closed loop bi-directional broadband Doppler compensation and channel equalization for single carrier high-speed underwater acoustic communication

In this paper, we propose a broadband Doppler estimation and compensation receiver, which combines a bi-directional decision feedback equalizer (DFE). Compared with the existing receivers, the proposed closed loop Doppler estimation and compensation receiver combined with a bi-directional DFE can not only estimate and compensate the broadband Doppler symbol-by-symbol, but also reduce the error propagation effect caused by DFE. Experimental results show that the performance of the proposed receiver can be improved in terms of output signal-to-noise ratio (SNR) and bit error rate (BER). Compared with the closed loop Doppler estimation and compensation receiver combined with the adaptive DFE, the performance of the proposed receiver can be improved by 1.17 dB in terms of output SNR at 1 kbps with the platform moving at up to 6 knots.