Tradeoff-HARQ Scheme for Full-Duplex SWIPT DF Relay

Abstract

The SWIPT (simultaneous wireless information and power transfer) DF (decoding and forwarding) relay system could achieve the purpose of both increasing revenue and reducing expenditure. By analysing the system model and transmission characteristics of full-duplex relay, this paper optimizes the retransmission slot structure to enhance the system performance. Firstly, the state transition model is established based on the analysis of the retransmission slot structure. Secondly, the state probability of each state and the transition probability between states are calculated to obtain the total data passing rate, energy transmission efficiency, and total transmission time. Thirdly, in order to compare the performance of various HARQ (hybrid automatic repeat request) schemes more effectively, JNTP (joint normalized throughput of information transmission and energy transmission) is constructed. Monte Carlo simulations finally confirm that the proposed tradeoff-HARQ scheme outperforms the regular-HARQ scheme in terms of JNTP: the performance of the tradeoff-HARQ scheme is 0.03883 higher than that of the regular-HARQ scheme when the total power limit is 20 dB and 0.00651 higher than that of the regular-HARQ scheme when the total power limit is 30 dB.