Blind CFO Estimation for Zero-Padded OFDM Over Underwater Acoustic Channels
In this paper, the authors studied the use of three existing blind CFO estimation algorithms for ZP-OFDM transmissions in underwater acoustic channels. They provided both numerical and experimental results. Simulations showed that the Y-G algorithm can perform as well as the null subcarrier based method, while having lower complexity, as far as the fractional part of CFO is concerned. When dealing with real data sets, the Y-G algorithm has to be modified and they further coupled it with an integer CFO estimator based on a few null subcarriers. Experimental results showed that the modified Y-G algorithm is a slightly worse than the null subcarrier based method for small to moderate-size constellations and becomes not effective for large constellations.