Research On Energy Efficient Hybrid Precoding Of Milimeter Wave MIMO System

As one of the most potential technology of the future wireless communication, Millimeter-wave communication received extensive concern and research. In this paper, the larger antenna array and the limited scattering of millimeter-wave channel are considered, and energy efficient hybrid precoding problems for millimeter-wave MIMO system are investigated. The main contents of this paper are summarized as follows:In Chapter 2, energy efficient hybrid precoding problem for single user millimeter-wave MIMO system is investigated. First, a perfect receiving processing is assumed, thus the optimization problem aims at maximizing the energy efficiency of the transmitter. Then, the hybrid precoding problem is equivalent to an Euclidean distance minimization problem, and is further equivalent to a sparse signal reconstruction problems. Numerical results show that the proposed hybrid precoding algorithm achieves near optimal energy efficiency, and the energy efficient hybrid precoding algorithm is outperformans the sum rate maximization algorithm in the high transmit power region.In Chapter 3, based on the achieved hybrid procoders In Chapter 2, MMSE hybrid combining problem is investigated. First, the original optimization problem is equivalent to a sparse signal reconstruction problems which has a weighting factor, and the hybrid combining algorithms which based on different sparse approximation algorithms are proposed. Then, a more effiective design order of precoding and combining is given. Numerical results show that all of the proposed combining algorithms achieve near optimal performance, and the one which based on the orthogonal matching pursuit algorithm achieves the best approximation effect.In Chapter 4, energy efficient hybrid precoding problem for millimeter-wave system in MIMO Interference channels is investigated. First, the multivariable optimizing problem is converted into an univariate precoding problem by simple variable substitution, and the energy efficient unitary precoder is achieved by a two-layer iteration algorithm. Then, the hybrid precoding problem is tansformed into a sparse signal reconstruction problem. Numerical results show that the energy efficient precoding algorithm achieves better energy efficiency when compared to the sum rate maximization algorithm, and all of the proposed hybrid precoding algorithms which based on different sparse approximation algorithms achieve near optimal performances.In Chapter 5, hybrid precoding problem for multicell multiuser millimeter-wave MIMO system is investigated, and maximizing the sum of the weighted energy efficiency is defined as a new criterion. First, the energy efficient unitary precoder is achieved through a two-layer iteration algorithm. Then, the hybrid precoding is converted into a simultaneous sparse signal reconstruction problem, and hybrid precoding algorithm which based on a simultaneous sparse approximation algorithm is proposed. Numerical results show that the energy efficient precoding algorithm for multicell multiuser millimeter-wave MIMO system effectively improves the energy efficient performance, and the simultaneous sparse approximation based hybrid precoding algorithm achieves near optimal system performance.