关键词: 全双工, 非线性能量收集模型, 剩余硬件损伤, 剩余自干扰, 吞吐量

Abstract: To comply to the non-linear output characteristic of energy harvesting(EH) circuits and non-ideal hardwares, a constant-linear-constant energy harvesting model was applied in a simultaneous wireless information and power transfer(SWIPT) -enabled full-duplex two way relay network which took residual hardware impairments(RHIs) into account. To reduce the impact of RHIs and residual self-interference(RSI) on the outage performance of relay networks, an optimization algorithm based on golden section search method is proposed for improving throughput. Firstly, considering the piecewise signal-to-noise-plus-distortion ratio(SNDR), the end-to-end outage probability was expanded by the law of total probability. The derivation method and method of substitution were used to convert the complex expression into a single integral, thus obtaining a closed form expression of the outage probability. The end-to-end outage probability is piecewise by the SNDR threshold, further identifying the overall system ceiling(OSC) caused by only RHIs. Then the system throughput derived from the outage probability was transformed into a function regarding the time switching(TS) ratio. Finally, after analyzing the monotonicity of the throughput function, the proposed algorithm was used to maximize the system throughput. Numerical simulations are provided to verify the piecewise end-to-end outage probability and better system throughput brought by optimization algorithm. Besides, it is shown that compared to linear EH models, the application of nonlinear EH models in full duplex mode results in system throughput decreasing at high SNDRs.

Key words: full-duplex, non-linear energy harvest models, residual hardware impairments, residual self-interference, throughput