Study On The Combination Of Antenna Selection And Interference Cancellation Technology In Massive MIMO Systems

Large-scale multiple-input multiple-output(MIMO)technology can improve system capacity performance without increasing system bandwidth and power consumption.Compared to conventional MIMO,it can fully use space resources.However,these performance improvements increase RF link costs.For large-scale MIMO systems,antenna selection technology is considered to be one of the effective solutions to compromise between system performance and high hardware costs.Due to the inter-user interference problem in multi-user MIMO systems,the interference may deteriorate the communication quality.For massive MIMO systems,interference cancellation technique is an efficient approach to overcome this problem.Based on the research of the above issues,this thesis combines antenna selection with interference cancellation technique in large-scale MIMO system.This solution can eliminate system interference,reduce hardware costs,and improve system performance.The main contributions of this thesis include the following aspects:(1)Firstly,the antenna selection technique and the linear precoding technique are used in a single-cell multi-user massive MIMO system.The combination of these two technologies can fully utilize the advantages of them,at the same time it can achieve near-optimal capacity while reducing hardware costs.This conclusion provides a theoretical basis for the marketization of large-scale MIMO technology.(2)For large-scale MIMO systems with two cells and multiple users,this thesis proposes a method that combines the downlink interference alignment technology with antenna selection technology.Simulation results show that the scheme achieves better performance than the Zero-Forcing(ZF)and Minimum Mean Square Error(MMSE)precoding solution,and this advantage is especially obvious in high SNR regime.(3)For three-cell multiple-user massive MIMO system,this thesis proposes an interference alignment algorithm and combines it with the antenna selection technique based on the Greedy Algorithm.Simulation results show that this scheme achieves higher capacity than ZF precoding solution.