缓存辅助的协作NOMA携能传输

Buffer-aided cooperative NOMA with power transfer

为提升多用户无线携能通信系统吞吐量,设计了一种缓存辅助的协作非正交多址接入(NOMA)携能传输方案,在平均/峰值功耗、用户速率、缓存队列稳定性等约束条件下,最大化系统平均吞吐量。为降低优化复杂度,引入Lyapunov方法,将长期平均优化问题转化为一系列时间离散的子优化问题,并提出了一种自适应传输与资源分配优化算法,能根据时变信道/缓存状态,动态优化工作模式、用户调度和功率分配。仿真结果表明,与已有方案相比,所提方案可显著提升平均吞吐量,且实现时延与吞吐量间性能的折中。

To improve the throughput of multiuser simultaneous wireless information and power transfer systems,a buffer-aided cooperative non-orthogonal multiple access scheme with power transfer was designed to maximize the average throughput under the constraints of average/peak power,user’s rate,and the buffer stability.To reduce the optimization complexity,the Lyapunov’s method was introduced to convert the long-term average optimization problem into a series of time-discrete subproblems,and an adaptive transmission and resource allocation optimization algorithm was proposed,where the working mode,the user scheduling and the power allocation were dynamically optimized according to the time-varying channel/buffer state.Simulation results demonstrate that compared with the existing schemes,the proposed scheme can significantly enhance the average throughput whilst achieving the tradeoff between the delay and throughput.