ADMM-Based Channel Estimation Methods for Millimeter Wave MIMO System

Millimeter wave (mmWave) communication techniques have been regarded as promising solutions for wireless communication networks. However, short wavelength of mmWave signals poses fundamental challenges in estimating wireless channels. This paper tackles the channel estimation problems for frequency selective mmWave imposed on a multiple-input and multiple-output (MIMO) systems. In particular, we leverage the low-rank and sparse properties of mmWave channel matrices. The alternating direction method of multipliers (ADMM) with a relaxation parameter in a symmetrical order is employed. The numerical results exhibit the superiority of proposed methodology in terms of mean-squared-error and spectral efficiency.