Research On The Precoding Scheme Of Massive MIMO

Cellular mobile communication technology has been rapid development in recent decades, from the early 1G to 4G now and then to the upcoming 5G, mobile communications with its own characteristics of convenient and the development mode of advance with the times, is good to adapt to the current needs of the information age and show a strong vitality. 5G is the abbreviation of fifth-generation, refers to the fifth generation mobile phone system which is currently under investigation. 5G is expected to be perfect standardization around 2020. Massive MIMO(also named Large scale MIMO) as the key technology of 5G is one of the hot research topic proposed in recent years, compared with the traditional MIMO, the BER performance of Massive MIMO and rate performance improves significantly. Beamforming as the most representative of the anti-jamming mode of Massive MIMO is the focus of research on Massive MIMO. This article is precisely under such background, in-depth study of the downlink precoding technique on large scale MIMO.We will consider a single cell massive MIMO downlink system, a base station equipment N antenna, service K the same time frequency resource of single antenna users, the user terminal is uniformly distributed in the radius of R cell. In this environment, we analyzed zero forcing(Zero forcing, ZF), maximum ratio transmission(Maximum ratiotransmission, MRT) and some of their derivative algorithm, MRT pre coding and ZF precoding are compared and analyzed, we found that ZF compared with MRT has higher power efficiency to achieve high data rate. Then we study the constant envelope(Constant-Envelope, CE) and its improved algorithms. We found that in N/M medium, compared with CE precoding in ZF pre coding and has obvious effect of promotion. We of these algorithm simulation analysis is carried out to prove our conclusion.