Research on Wireless Communication Channel Estimation Method for Multiple-input Multiple-output System
The multiple-input multiple-output (MIMO) system has extensive applications in wireless communication. This paper mainly studied the channel estimation methods for the MIMO systems. Firstly, the MIMO system and two traditional channel estimation methods, i.e., least squares (LS) and minimum mean square error (MMSE), were introduced. Then, the orthogonal matching pursuit (OMP), compressive sampling matching pursuit (CoSaMP), and stagewise weak orthogonal matching pursuit (SWOMP) methods were introduced. The SWOMP method was added with a step size parameter to obtain the improved SWOMP (ISWOMP) method. The simulation experiment found that the normalized mean squared error (NMSE) and bit error rate (BER) of channel estimation were different under different number of pilot frequency and signal-to-noise ratios (SNRs). The CS methods outperformed LS and MMSE methods in channel estimation. The ISWOMP method had the smallest NMSE and BER. Taking SNR = 20 dB as an example, the NMSE of the ISWOMP method was 0.0021, which was 97.87% smaller than the OMP method and 64.41% smaller than the SWOMP method. The experimental results verify the reliability of the ISWOMP method for channel estimation. The ISWOMP method can be applied in real MIMO systems.
Keywords: multiple-input multiple-output system, wireless communication, channel estimation, compressed sensing