Abstract:

For orthogonal frequency division multiplexing (OFDM) underwater acoustic (UWA) communication systems, the least square (LS) channel estimation algorithm is greatly influenced by the noise, and a new error is introduced due to null subcarriers for the discrete Fourier transform (DFT) interpolation algorithm. In view of the above problems, an LS-DFT channel estimation algorithm is proposed. First，the pilot channel estimation is done by the LS algorithm. Secondly, the above data are calculated through the DFT for noise reduction processing. After that, the data replacement is finished, and a group of new pilot channel data is acquired. Finally, linear interpolation is used to get a valuation in the other data subcarrier channel by the new pilot data. The theoretical analysis and computer simulation results show that the algorithm can effectively improve the performance of the system with a lower complexity.