Sparse Channel and Antenna Array Performance of Hybrid Precoding for Millimeter Wave Systems

Fast data rates and higher capacity are the major promises in the communication network for the next generation. Due to technology advancement and market demands, wireless communication systems have undergone a revolution from past years. To achieve a manifold increase in capacity of the system, precoding is used at the base station. Now a day, hybrid precoding is in the air of wireless communication due to its high average achievable rate and low hardware complexity. However, finding the optimal solution to such hybrid precoding requires solving a challenging combinative problem. A known algorithm “orthogonal matching pursuit (OMP)” can provide a reasonable solution at the cost of computational complexity. In this paper, an algorithm based on the principle of orthogonal matching pursuit (OMP) is used for hybrid precoding in mmWave systems having large antenna arrays and channel sparsity. This paper gives the optimal solution for different values of channel sparsity and the number of transmitting/receiving antennas that approaches to approximate optimal unconstrained precoder. These solutions are shown by the simulation results of OMP algorithm-based hybrid precoder and show that they allow mmWave systems to approach their unconstrained performance limits. Therefore, to meet the requirements of the 5G network, the mmWave frequencies can be considered as one of the advanced technologies.