A channel estimation algorithm for train wireless communication system based on improved singular value decomposition linear least mean square error

Aiming at the problem of difficulty in accurately estimating the OFDM channel in wireless communication of high-speed trains, an improved SVD-LMMSE channel estimation method for OFDM systems is proposed. This article first introduces the OFDM system model, and then introduces several typical channel estimation methods: LS algorithm, MMSE algorithm, LMMSE algorithm, and SVD-LMMSE algorithm. Based on the above, a SVD-LMMSE channel estimation method based on improved DCT is proposed. This method utilizes the DCT algorithm and wavelet transform to decompose the channel autocorrelation matrix, achieving effective separation of channel noise components; Then, using singular value decomposition techniques to reduce the complexity of high-frequency noise sequences; Next, reconstruct the effective signal to obtain the denoised signal matrix; Finally, simulation tests were conducted using MATLAB, and the results showed that the error rate and mean square error performance of the channel estimation method were improved to a certain extent.