大规模MIMO系统多用户PSK调制方案的优化

针对超可靠低时延通信短包传输特征，在大规模多输入多输出（Multiple-Input Multiple-Output, MIMO）上行链路系统中，利用较低导频开销来设计相移键控（Phase Shift Keying, PSK）调制方案，并对该方案进行优化兼顾无线链路传输的可靠性。首先，在接收端构建基于最小欧式距离的非相干检测器；然后，基于旋转PSK星座来设计多用户空时调制方案，以此构造信号可靠传输方案；最后，利用信号间最小欧式距离最大化准则设计发射功率与PSK星座旋转角度的联合优化机制。仿真结果表明，所提方案能够较大幅度地提升已有方案的性能：对于二进制相移键控（Binary Phase Shift Keying, BPSK）,当信噪比等于-6 dB且接收天线数目为128时，系统误符号率可降低至10^-7;对于4PSK,当信噪比为0 dB且接收天线数目为128时，系统误符号率可降低至10^-3。

Optimization of multi-user PSK modulation scheme for massive MIMO system

A phase shift keying(PSK)modulation scheme is designed in a massive multiple-input multiple-output(MIMO)uplink system for the short packet transmission in ultra-reliable low-latency communications.The proposed scheme uses a lower pilot overhead and at the same time improves the reliability of wireless transmission.In detail,a noncoherent detector based on the minimum Euclidean distance is constructed at the receiver.With the rotated PSK constellations,a multi-user space-time modulation scheme is designed to build a reliable transmission scheme.After that,a joint optimization framework of transmit power and rotation angle of PSK constellation is established by maximizing the minimum Euclidean distance between signals.The simulation results show that the proposed scheme can significantly improve the existing referenced scheme s error performance.Specifically,for binary phase shift keying(BPSK),when the signal-to-noise ratio(SNR)is-6 dB and the number of receiver antennas is 128,the symbol error rate degrades to 10^-7.For 4PSK,when the SNR is 0 dB and the number of receiver antennas is 128,the symbol error rate degrades to 10^-3.