Performance analysis of multi-relay SWIPT systems with random placement of nodes

To facilitate the demand for a higher spectrum and power efficiency, relay-aided cooperative communication is considered as one of the most efficient techniques for achieving high data rate and coverage. In this work, we consider a scenario where the relays are not equipped with fixed batteries but collect the required energy (for processing and transmission purposes) via simultaneous wireless information and power transfer (SWIPT). To investigate the beneficial effect of the presence of many energy harvesting relays, we propose an analytical evaluation of the overall amount of power that can be received by the destination under a large class of propagation and fading models. The results show that, although the power received at the destination by the relays is obviously lower than the amount of the power from the direct source-destination link, this effect can be significantly reduced in dense node scenarios.