New Hybrid Precoding Algorithm Based on Sub-connected Structure

Abstract

Millimeter wave communication can provide higher spectrum,so that it’s the key technology of 5G network,but it will also have greater road loss.Large scale antenna array and directional beamforming technology can solve this problem effectively.However,with the increase of the number of antennas,the cost of hardware and energy of traditional digital precoder is very high,so hybrid precoder is needed to overcome this difficulty.However,the power consumption of the algorithm is high in the fully-connected structure.Therefore,a new hybrid precoding algorithm based on sub-connected structure is proposed in this paper.Firstly,the transmit antenna array is divided into several independent sub-arrays,then the analog precoding matrix of each sub-array is designed,and the spectral efficiency of each sub-array is optimized in turn to maximize the total spectral efficiency.Finally,based on the obtained analog precoding matrix,the digital precoding matrix is solved by the least square method.Simulation results show that compared with the orthogonal matching pursuit algorithm,the difference between the two algorithms is no more than 3bps/Hz,but the energy efficiency can be improved by 23.8%.Compared with the power iterative algorithm,the spectral efficiency of the proposed algorithm is higher,and the energy efficiency can be improved by 4%.Therefore,the proposed algorithm has good practical application value.

Keywords

• large scale mimo|hybrid precoding|sub-connected|spectrum efficiency|energy consumption