In cooperative communication, relay reduces the stored energy for its own transmission due to the energy consumption for forwarding the information from source node. In this paper, simultaneous wireless information and power transfer (SWIPT) for OFDM-based cooperative communication is proposed to save the relay’s energy by harvesting the radio frequency (RF) energy from source node. Subcarrier allocation based SWIPT (SA-SWIPT) is designed to use different subcarrier sets for information decoding and energy harvesting. In the first phase, the relay uses the SA-SWIPT to receive information and energy from source node. And in the second phase, the relay forwards the information both from source node and itself to the destinations using the energy collected from source node. The transmission rates of the relay in DF and AF modes are maximized by jointly optimizing subcarrier allocations and subcarrier powers, respectively, while ensuring the required transmission rate of source node and the energy supply of relay. An efficient iterative optimization algorithm is proposed to solve the proposed optimization problem through Lagrangian dual decomposition. Simulation results show the convergence of the optimization algorithm after very few iterations and explains the potential benefits for using SA-SWIPT in the OFDM-based cooperative communication.

在协作通信中，由于减少了从源节点转发信息的能耗，因此中继减少了自身传输所存储的能量。本文提出了一种用于基于OFDM的协作通信的同时无线信息和功率传输（SWIPT），以通过从源节点收集射频（RF）能量来节省中继器的能量。基于子载波分配的SWIPT（SA-SWIPT）设计为使用不同的子载波集进行信息解码和能量收集。在第一阶段，中继使用SA-SWIPT从源节点接收信息和能量。在第二阶段，中继使用从源节点收集的能量将信息从源节点及其本身转发到目的地。通过分别优化子载波分配和子载波功率来最大化DF和AF模式下中继器的传输速率，同时确保所需的源节点传输率和中继器的能量供应。提出了一种有效的迭代优化算法，通过拉格朗日对偶分解来解决所提出的优化问题。仿真结果表明，经过很少的迭代，优化算法就会收敛，并说明了在基于OFDM的协作通信中使用SA-SWIPT的潜在好处。提出了一种有效的迭代优化算法，通过拉格朗日对偶分解来解决所提出的优化问题。仿真结果表明，经过很少的迭代，优化算法就会收敛，并说明了在基于OFDM的协作通信中使用SA-SWIPT的潜在好处。提出了一种有效的迭代优化算法，通过拉格朗日对偶分解来解决所提出的优化问题。仿真结果表明，经过很少的迭代，优化算法就会收敛，并说明了在基于OFDM的协作通信中使用SA-SWIPT的潜在好处。