Energy-Assisted Information Detection for Simultaneous Wireless Information and Power Transfer: Performance Analysis and Case Studies

In simultaneous wireless information and power transfer (SWIPT), practical receiver architectures consisting of an information receiver and an energy harvester have been proposed in place of an ideal receiver capable of performing two tasks simultaneously using the same circuits. In this paper, we present a novel receiver architecture design incorporating an interplay between the information receiver and the energy harvester to enhance the performance of the practical SWIPT receiver. In particular, the energy level of the received signal monitored at the energy harvester is fed back to the information receiver to assist information decoding at the information receiver. The symbol-error-rate (SER) and diversity analyses show that the proposed receiver architecture could yield a higher diversity order for unconventional constellations where any two distinct symbols have distinct energy levels, and the same diversity order for conventional modulations. Simulation of PAM and QAM modulations verifies the analysis, shows the improved SER performance of the proposed receiver architecture, and illustrates the energy-dimension-augmented decision regions. Some insights into designing enhanced practical SWIPT receivers are provided as a result.