Non-Orthogonal Ratio Control and Power Allocation Optimization Algorithm for Multi-User Full-Duplex Cooperative PNOMA Systems
In traditional NOMA systems,signals between the near and far user equipment (UE) in the time and fre-quency domain are fully overlapped to obtain the highest spectrum efficiency,but interference between the UEs has become a critical issue. Partial NOMA (PNOMA) systems can significantly reduce the interference between the UEs because the NOMA mechanism is only partially adopted in the whole frequency band. Compared to traditional NOMA systems,PNO-MA systems can significantly reduce the negative impact of imperfect successive interference cancellation (ipSIC) on the system sum rate. Based on the full-duplex cooperative NOMA (FD-CNOMA) and PNOMA system,this paper proposes a full-duplex cooperative PNOMA (FD-CPNOMA) system to reduce the interference between the UEs and accordingly im-prove the achievable system rate. Considering the non-ideal interference cancellation in practice and a FD-CPNOMA sys-tem consisting of one base station and multiple UEs,this paper proposes an optimization algorithm for UE pairing,non-or-thogonal ratio control and power allocation. In addition,closed-forms of UE outage probability and approximate closed-forms of average achievable rates in this model are derived. Simulation results show that the performance of the proposed UE pairing scheme is better than the other three schemes,the maximum achievable rates of PNOMA systems are all better than the conventional NOMA systems,and the maximum achievable rate of FD-CPNOMA system is 95.42％ and 44.06％ higher than that of half-duplex cooperative NOMA (HD-CPNOMA) and PNOMA systems respectively with low signal-to-noise ratios (SNR). The proposed FD-CPNOMA system provides a better tradeoff between the fairness and average reach-able rate among the UEs at high SNR.
万方数据
维普
