Energy-efficient hybrid precoding for millimeter wave MIMO systems

In this paper, we investigate energy-efficient hybrid precoding for the Millimeter Wave (mmWave) multi-input multi-output (MIMO) systems. The considered multivariate optimization problem is hard to tackle because of the non-convex objective function and constraints. To solve the intractable problem, we propose a two-step optimization algorithm to obtain a near-optimal solution. The original multivariate optimization problem is first transformed into an equivalent univariate optimization problem whose solution is a optimal single precoder. Then, by minimizing the Euclidean distance between the optimal single precoder and the hybrid precoder, a near-optimal hybrid precoder are obtained via orthogonal matching pursuit (OMP) based algorithm. Numerical results validate that the energy efficiency (EE) performance of the proposed hybrid precoding algorithm is approximating to the optimality, and it obviously outperforms the spectral efficient hybrid precoding algorithm at the middle-high transmit power. In addition, we show the impacts of different system parameters on the energy-efficient performance.