基于MIMO通信注水功率分配算法的信道容量研究  

Research on Channel Capacity Based on Water-FillingPower Allocation Algorithm in MIMO System

作　　者：高云波[1] 李翠然[2] 程璇 何荣 田智愚 GAO Yunbo;LI Cuiran;CHENG Xuan;HE Rong;TIAN Zhiyu(School of Automation and Electrical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;School of Electronic and Information Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Lanzhou Railway Design Institute Group Co.,Ltd.,Lanzhou 730030,China;Lanzhou Rail Transit Co.,Ltd.,Lanzhou 730000,China)

机构地区：[1]兰州交通大学自动化与电气工程学院,兰州730070 [2]兰州交通大学电子与信息工程学院,兰州730070 [3]兰州铁道设计院集团有限公司,兰州730030 [4]兰州市轨道交通有限公司,兰州730000

出　　处：《兰州交通大学学报》2023年第4期58-65,共8页Journal of Lanzhou Jiaotong University

基　　金：国家自然科学基金(62161016,52167013);甘肃省自然科学基金(20JR10RA210);甘肃省科技计划资助(20JR10RA273);兰州交通大学-天津大学联合基金(2022064);光电技术与智能控制教育部重点实验室(兰州交通大学)开放课题(KFKT2019-)。

摘　　要：在城市轨道交通车辆段场景下,列车的通信需求巨大。针对传统城轨车地通信网络分配资源时未考虑接收端信道状态信息的问题,设计了一种多输入多输出通信注水功率分配算法。首先,分析城轨中基于长期演进的分布式控制系统车地通信网络结构和资源分配模式;其次,基于实际通信需求建立优化模型,利用拉格朗日乘子法求解注水算法的最优分配功率;最后,建立多输入多输出通信注水功率分配算法的通信模型,并推导其信道容量以及功率分配值。仿真结果表明:相比等功率分配算法,注水算法可以明显提高城轨车地通信网络的信道容量,且具有更小的误比特率;多输入多输出通信注水功率分配算法能够进一步提升信道容量,但当信噪比达到一定值后,这种增益逐渐逼近等功率分配算法的信道容量;考虑列车的实际结构,设计可选用的最佳收、发天线组合为4发4收。In the urban rail depot scenario,the communication demand for trains is huge.Aiming at the problem that the receiver channel status information is not considered when allocating resources in the train-to-ground communication network of tradition urban rail,this paper designs a water-filling power allocation algorithm in multi-input multiple-output system for it.Firstly,the train-to-ground communication network structure and resource allocation mode in urban rail based on distributed control system of long-term evolution are analyzed.Secondly,an optimization model is established based on actual communication requirements,and the Lagrange multiplier method is used to solve the optimal power allocation of water-filling algorithm.Finally,the communication model based on the water-filling algorithm in multi-input multiple-output system is established,and its channel capacity and power allocation value are derived.The simulation results show that compared with the equal power allocation algorithm,the water-filling algorithm can significantly improve the channel capacity of network,and has a smaller bit error rate;The water-filling power allocation algorithm in multi-input multiple-output system can further improve the channel capacity,but when the signal-to-noise ratio reaches a certain value,this gain gradually approaches the channel capacity of the equal power allocation algorithm;Considering the actual structure of the train,the optimal combination of transmitting and receiving antennas is proposed to be 4 transmitting antennas and 4 receiving antennas.

关 键 词：车地通信网络 多输入多输出 功率分配 注水算法 信道容量 

分 类 号：U285.21[交通运输工程—交通信息工程及控制]