Research on four-point Bessel interpolation algorithm in MIMO-OFDM systems and its application in B channel model of M.1225 standard

A three-dimensional (space, time and frequency) orthogonal comb pilot scheme is designed to dissolve the problem of the interference of pilot signals between multiple antennas in MIMO-OFDM systems. The MIMO-OFDM channel estimation can be transformed into the single antenna channel estimation for OFDM systems using the pilot scheme. The scheme transmits the pilot information for the channel estimation on the part of the sub-channel and the time domain of each sending antenna, which greatly improves the rate of data transmission and shows good ability of real-time performance. Based on the channel estimation with LS algorithm roughly, a novel four-point Bessel interpolation algorithm is proposed to make the channel estimation precisely, and compared with second-order Gaussian interpolation algorithm and first-order linear interpolation algorithm. The results of simulation show that the pilot scheme is feasible. When the normalized mean square error reaches 2×10^-5 in B channel model of M.1225 standard, the SNR (Signal Noise Ratio) of four-point Bessel interpolation algorithm is 3.5dB and 4dB higher than that of the second-order Gaussian interpolation algorithm and the linear interpolation algorithm, respectively.