Store-then-cooperate: Energy harvesting scheme in cooperative relay networks

The energy efficiency of a system determines its operational sustainability. Energy harvesting (EH) is a crucial technology for a variety of wireless systems that have limited access to a reliable electricity supply. In this paper, the design of a multiple access relay system (MARS) using EH is considered. We assume that the sources and relay have no embedded power supply but rechargeable energy storage devices. Thus, each node is powered by harvesting the energy from the RF signals broadcasted by an access point (AP), and it operates in store-then-cooperate (STC) mode. We present link level performance by using the physical layer network coding for energy harvesting schemes of EH and STC and its outage probability analysis. The schemes presented in this paper achieve symbol error rate (SER) performance approaching that of a fixed power supply and contribute significantly to sustaining the energy in the system while maintaining a constant throughput.