直达链路下的能量采集中继选择系统的吞吐量分析

针对三节点传输系统,研究了基于功率分配能量采集的全双工放大转发协作中继方案。考虑源和目的地之间存在直达链路,全双工中继节点采用天线选择技术以最小化中继自干扰,目的节点采用最大比合并技术以最大化目的地接收信噪比。在延迟受限传输模式下,运用高斯-切比雪夫积分推出了系统吞吐量的近似闭合表达式。在延迟容忍传输模式下,运用凸优化推出了系统吞吐量下界的闭合表达式。在多中继情况下考虑了最佳中继选择策略和机会式中继选择策略。数值分析和蒙特卡洛仿真表明,增加中继个数或者减小速率阈值均能提高系统吞吐量。

Throughput Analysis of Energy Harvesting Relay Selection Systems with Direct Link

According to the three-node transmission system, the amplify and forward cooperative relay scheme is investigated by combining power splitting-based energy harvesting and full-duplex technologies. Consider a direct link between the source and destination, the full-duplex relay node adopts antenna selection technology to minimize the relay self-interference, and the destination node adopts the maximum ratio combining technology to maximize the received signal-to-noise ratio at the destination. Under the delay-limited transmission mode, the approximate closed expression for systematical throughput is derived by using Gaussian-Chebyshev quadrature. Under the delay tolerant transmission mode, the closed form expression for systematical throughput lower bounded is derived by using Convex optimization. The optimal relay selection scheme and the opportunistic relay selection scheme are considered in the case of multiple relays. Numerical analysis and Monte Carlo simulations show that, the systematical throughput can be improved whether by increasing the number of relays or decreasing the rate threshold.