储能发送模式下全双工双向中继系统的和速率优化

Sum-rate Optimization for Full-duplex Two-way Relaying Systems Under Energy-Saving-then-Transmitting Mode

针对一类中继能量受限的放大转发全双工双向中继系统,提出了一种基于储能-发送模式的无线信息与能量同时传输方案.该方案在满足中继收集能量和节点传输功率等约束下,通过联合优化传输功率与时间切换系数等参数实现系统的和速率最大化.此优化问题在数学上是非凸的,很难或不可能求得其最优解.为此,首先提出分别优化传输功率和时间切换系数,然后利用收敛迭代方法求得原问题的次优解,最后,仿真结果验证了所提方案的有效性.与现有算法相比,所提联合优化算法能够显著提高系统的和速率.

For an amplify-and-forward based full-duplex two-way relaying(FD-TWR)network with an energy-constrained relay,a save-then-transmit protocol in simultaneous wireless information and power transfer(SWIPT)system was proposed.A utility optimization problem aiming to maximize the sum-rate by jointly optimizing the transmit powers and the time switching ratio was considered.Since the formulated joint optimization problem is nonconvex,it is difficult or even intractable to obtain the global optimal solution.To overcome this issue,the objective problem was decoupled into two sub-problems,in which,one is to optimize the transmit powers while another one to optimize the time switching ratio.Then,the suboptimal solution is obtained with the proposed convergent iterative algorithm.Finally,simulation results confirms the effectiveness of the proposed scheme.Compared with the existing works,the proposed algorithm achieves significant improvement of the sum-rate.