System and Design for Selective OFDM SWIPT Transmission

Simultaneous wireless information and power transfer (SWIPT) augments a wireless device's capability to transmit data by adding a harvesting component to the standard information processing receiver. With SWIPT, both information processing and energy scavenging are combined to allow a SWIPT device to become its own recurrent power source. This article proposes and analyzes the functionality of a novel selective orthogonal frequency-division multiplexing (OFDM) receiver architecture. The architecture leverages the OFDM signal structure to extract the cyclic prefix (CP) of the signal for energy harvesting and selectively harvest a fraction of the received signal for increase energy storage. This article also evaluates the rate-energy (R-E) tradeoff of the system as a means for analyzing the switching time's impact on rate and energy. Additionally, this article examines the feasibility of harvesting sufficient energy to power the OFDM processing portion of the receiver. To understand the feasibility, an optimization problem is developed to minimize the portion of the information signal used for harvesting while ensuring sufficient energy is harvested to perform the processing. To facilitate the evaluation, Monte Carlo simulations are run presenting system level R-E tradeoff and feasibility performance. Selective OFDM transmission is found to provide improved energy harvesting and sustainability.