基于连续干扰消除和交替方向乘子法的混合预编码设计

Design of hybrid precoding with successive interference cancellation and alternating direction method of multipliers

为解决毫米波多天线系统大量移相器(PS)引起的高功耗问题,设计了一种新型动态连接结构,以最大化频谱效率为目标提出了连续干扰消除(SIC)和连续干扰消除−交替方向乘子(SIC-ADMM)2种混合预编码方案。SIC将总速率问题分解为不同射频链路的子速率问题,先对模拟部分进行逐次迭代,转化为低维度等效矩阵后再对数字部分进行求解。SIC-ADMM是对SIC的改进,通过研究多变量子速率问题实现算法的快速收敛,并能有效地降低计算复杂度。仿真结果表明,所提方案在频谱效率和能量效率方面优于现有典型预编码方案,且更适用于大规模天线系统。此外,当关闭一定比例PS后,所提方案能够通过牺牲少量频谱效率换取能量效率的大幅提升。

To solve the problem of large power consumption caused by a large number of phase shifter(PS)in millimeter wave multi-antenna systems,a new type of dynamic connection structure was designed.With the goal of maximizing spectrum efficiency,two hybrid precoding schemes,successive interference cancellation(SIC)and successive interference cancellation-alternating direction multiplier(SIC-ADMM),were proposed.In SIC scheme,the sum-rate problem was decomposed into multiple sub-rate problems of different radio frequency links,the analog part was solved by iteration,and the digital part was solved by a low-dimensional equivalent matrix.Based on SIC scheme,an improved SIC-ADMM scheme was further proposed by studying the multi-variable sub-rate problem to achieve rapid convergence and reduce computational complexity effectively.The simulation results show that the proposed schemes have good spectrum and energy efficiencies by comparison with the existing schemes,and are more suitable for large-scale antenna systems.In addition,when a certain percentage of PS is turned off,the proposed scheme can greatly improve energy efficiency by sacrificing a small amount of spectrum efficiency.