Subcarrier-Pairing-Based Resource Optimization for OFDM Wireless Powered Relay Transmissions With Time Switching Scheme
Subcarrier-Pairing-Based Resource Optimization for OFDM Wireless Powered Relay Transmissions With Time Switching Scheme
复制标题
具有时间切换方案的 OFDM 无线供电中继传输的基于子载波配对的资源优化
DOI：
10.1109/tsp.2016.2628351
复制
发表时间：
2017
影响因子：
5.4
通讯作者：
Wang Shuqiang
中科院分区：
文献类型：
--
作者：
Shen Yanyan;Huang Xiaoxia;Kwak Kyung Sup;Yang Bo;Wang Shuqiang
在本文中，我们研究了正交频分复用中继传输的联合资源优化，其中中继使用时间切换（TS）方案进行无线信息和功率传输。我们的目标是通过调整子载波配对（SP）、源传输功率、中继传输功率和 TS 因子，在几个约束下最大化总速率。与之前大多数忽略中继信号接收和处理能耗的研究不同，我们考虑了现实的能耗模型。我们将联合资源分配问题表述为混合整数非线性规划问题，该问题一般很难求解。首先，我们给出所考虑问题的可行条件。基于这个条件，我们证明有序SP是最优SP，因此SP和资源分配问题（RRAP）的其余部分可以分别求解，而不损失最优性。然后，提出了一种搜索算法来寻找RRAP的全局最优解。为了提高效率，提出了一种将搜索区域缩小的方法，并证明该方法包含最优解。接下来，为了进一步降低计算复杂度，我们巧妙地将 RRAP 转化为一个等效问题，其中目标函数是 D.C. 函数（凹函数的差分）。通过利用部分凸结构，我们提出了一种高效快速的算法。最后，仿真验证了所提算法与相关算法相比在总速率方面的优越性能。
In this paper, we investigate the joint resource optimization for orthogonal frequency division multiplexing relay transmissions, where the relay uses time switching (TS) scheme for wireless information and power transfer. We aim to maximize the total rate under several constraints by adjusting the subcarrier pairing (SP), the source transmission power, the relay transmission power, and the TS factor. Different from most of the previous works that ignore the energy consumption for signal receiving and processing at relay, we take into account a realistic energy consumption model. We formulate the joint resource allocation problem as a mixed integer nonlinear programming problem, which is generally difficult to solve. First, we give the feasible condition of the considered problem. Based on this condition, we prove the ordered SP is the optimal SP, and thus SP and the rest of the resource allocation problem (RRAP) can be separately solved without loss of optimality. Then, a searching algorithm is proposed to find the global optimal solution to the RRAP. To improve the efficiency, a method is proposed to reduce the searching region to a smaller one, which is proven to contain the optimal solution. Next, to further reduce the computational complexity, we subtly transform the RRAP to an equivalent problem, where the objective function is a D.C. function (difference of concave functions). By exploiting the partial convex structure, we propose an efficient and fast algorithm. Finally, simulations verify the superior performance of the proposed algorithms comparing with related ones in terms of total rate.