An Adaptive LMMSE Interpolation Algorithm for Channel Estimation in LTE-Advanced Systems

Abstract

The traditional LMMSE interpolation algorithm assumes that the terminal knows the channel power delay profile (PDP), which is not consistent with the actual situation. This paper proposes an improved LMMSE interpolation algorithm based on RMS estimation. The time-delay parameters of channel first are estimated by pilots, then LMMSE interpolation process in frequency domain is completed by LUT (looking up table) for selection of corresponding frequency domain interpolation matrix. This solves the difficulty in acquiring the second-order channel statistics in the traditional LMMSE interpolation algorithm, and avoiding the real-time inversion process of matrices. Simulation results demonstrate that this method can reduce the complexity and show a good performance of BER and MSE, thus it is more suitable for practical application.