Reliability Analysis of MRC Diversity Reception System Based on LS and MMSE Channel Estimation

Multipath fading will reduce the reliability of the Maximum Ratio Combining(MRC) diversity reception system. To improve the reliability of the system with lower complexity, this paper studies the influence of the number of antennas on the bit error rate(BER) of the MRC diversity reception system based on least squares (LS) and minimum mean square error (MMSE) estimation, and proposes an improved MRC algorithm based on pilot signal attenuation. Firstly, the attenuation matrix is calculated based on the energy attenuation of the pilot symbols. Then the combined weight matrix of the signals is calculated by the interpolation algorithm, and finally, the signals of all channels are combined. The simulation results show that when the signal-to-noise ratio(SNR) is 6 dB and the number of receiving antennas is 4, 8, and 16, respectively, the improved algorithm reduces the BER of the system based on LS estimation by 15%, 19% and 25%, respectively, and reduces the BER of the system based on MMSE estimation by 12%, 17% and 21%, respectively. The proposed algorithm improves the system's reliability with lower complexity, and its performance improves with the increase in the number of receiving antennas.