LS OFDM channel estimation based on path searching

A novel pilot-aided channel estimation algorithm for the OFDM system is proposed. Multipath delays in the time domain are searched based on the least square (LS) criteria and path gains are estimated using the LS estimation algorithm. Frequency channel coefficients are obtained through the Fourier transform. A serial path searching algorithm is proposed to reduce the computation of path searching. Estimation results in the HF OFDM communication system show that the path searching algorithm can effectively work under the low SNR condition. The influence of the searching path number is evaluated and it must be set equal to or more than the multipath number of real channel.