MIMO-NOMA系统中短包传输的功率分配方法

多输入多输出非正交多址接入(multiple input and multiple output-non-orthogonal multiple access,MIMO-NOMA)技术能够增加设备连接数量,有效提高系统的频谱效率,针对超可靠低时延应用业务中需要短包传输,而多用户簇的MIMO-NOMA系统同一簇用户对内远用户的吞吐量较低的问题,利用奇异值分解和最大比合并的方法消除簇间干扰,考虑近用户解码远用户的块错误概率低于给定阈值条件下,利用交替迭代算法联合优化簇内用户的发送功率和最大可达传输速率,实现远用户吞吐量的最大化。仿真结果表明与短包传输MIMO正交多址接入(orthogonal multiple access,OMA)系统相比,在保证块错误概率低于10^-5的条件下,远用户的吞吐量提高了32%。

Power allocation method for short packet transmission in MIMO-NOMA system

Multiple input and multiple output-non-orthogonal multiple access (MIMO-NOMA) could increase the number of device connections and improve the spectrum efficiency of the system effectively. Short-packet communication is required for ultra-reliable low-latency application services, while the far-user has lower throughput of user pairs of a cluster in the multi-user cluster MIMO-NOMA system. This paper eliminates inter-cluster interference through singular value decomposition and maximum ratio combining. Considering that the block error probability of the near-user decoding far-user is lower than a given threshold, the transmission power and the maximal achievable transmission rate of user pairs in a cluster are jointly designed to maximize the throughput by the alternate iterative algorithm. The numerical results show that compared with the MIMO-orthogonal multiple access(OMA) scheme in short packet transmissions, the throughput of the far-user is improved by 32% under the condition that the block error probability is lower than 10^-5.