基于混合精度ADC量化的大规模MIMO系统能效联合优化算法

Energy efficiency joint optimization algorithm for mixed-ADC massive MIMO systems

针对在接收端采用混合精度的数模转换器(analog-to-digital converter,ADC)的大规模MIMO系统上行链路,提出一种能效优化算法。在采用最大比合并(maximum ratio combining,MRC)检测算法的基础上,推导得到系统上行链路能效的近似闭式表达式。首先确定高精度ADC的占比率,再以低分辨率ADC的量化精度、用户的发射功率和基站端天线数为优化目标的3个变量进行交替迭代得出最优的能效值;并进一步通过调整高精度ADC的占比率分析其对能效和频效的影响。仿真结果表明,所提算法具有较高的能效值,并且可以通过调整占比率实现能效与频效更好地折中。

An energy efficiency optimization algorithm was proposed for the uplink of massive MIMO system with mixed precision analog-to-digital converter(ADC)at the receiver.Based on the maximum ratio combining detection algorithm(MRC),the approximate closed-form expression of system uplink energy efficiency was derived.Firstly,the proportion of high-precision ADC was determined,and then the quantization accuracy of low-resolution ADC,the user’s transmission power and the number of antennas at the base station was taken as the optimization objectives to alternately iterate to obtain the optimal energy efficiency value.Furthermore,the influence on energy efficiency and spectrum efficiency was analyzed by adjusting the proportion of high-precision ADC.The simulation results show that the proposed algorithm has high energy efficiency,and can achieve a better balance between energy efficiency and spectrum efficiency by adjusting the proportion of high-precision ADC.