低分辨率ADCs大规模MIMOAF中继系统性能分析

Performance Analysis of Massive MIMO AF Relaying Systems with LowResolution ADCs

在全双工大规模多入多出(massive MIMO)中继系统中,大量基站天线的数模转换给系统带来的硬件损伤和能量消耗,并且系统的性能可能会受到环路干扰的影响。为此,基于最大比传输/合并预处理方案,对多用户全双工massive MIMO放大转发中继系统进行研究,该系统由massive MIMO基站和多对单天线用户组成,massive M IM O基站采用低分辨数模转换且工作在全双工模式。通过随机矩阵理论,获得任一用户对各态历经速率的闭式解,并分别研究3种不同功率分配方案下的系统渐近特性。性能分析结果表明,当信源发射功率为常量且基站的发射功率与基站传输天线成反比时,系统能同时有效地遏制环路干扰和低分辨率ADCs的影响,而当信源和基站的发射功率同时与天线数成反比时,系统可抑制环路干扰的影响,但不能抑制量化噪声的影响。

In full-duplex massive Multiple Input Multiple Output（massive MIMO） relaying systems, the employment of numerous Analog to Digital Converters（ADCs） at massive MIMO relay leads to extremely high hardware cost and energy consumption. Moreover, the system performance can be further affected due to the loop interference. Therefore, based on maximum-ratio-transmission/maximum-ratio-combining processing schemes, this paper studies a multi-user full-duplex massive MIMO Amplify and Forward（AF） relaying system with low-resolution ADCs,which consists of large numbers of base station and multi-pairs antennas users, massive MIMO base station uses low-resolution ADCs and runs on full- duplex mode. Through random matrix theory, it performs the analysis of the achievable spectral efficiency of each user, which is given with closed-form expression. Based on the derivations the asymptotic analysis of spectral efficiency are performed under three different power-scaling schemes. Performance analysis results show that both the impact of loop- interference and the low-resolution ADCs on achievable spectral efficiency can be restricted effectively only under the power-scaling scenario where the relay＇ s transmit power is scaled down with the number of transmit antennas at relay while the one of sources is fixed. On the contrary, under the scenario where the transmit powers of both source and relay are scaled down with the number of antennas, only the effect of loop-interference is restricted but the one of low- resolution ADCs remains.