Scheme Design of SR-DCSK-WPC System With Energy Buffer in RIS-Assisted Design

To address the issue of obstacles in wireless channels, this paper proposes a time-division switching SR-DCSK-WPC scheme based on reconfigurable intelligent surface (RIS)-assisted communication. The scheme consists of an energy source (ES) transmitter, a RIS, and a terminal node D with an energy buffer. Firstly, the ES transmits an energy signal composed of multiple chaotic sequences. This energy signal powers the terminal node, and the proportion coefficient of the energy signal is adjusted by controlling the repetition count of the chaotic sequences. Secondly, the RIS adjusts the amount of transmitted energy and assists in bypassing obstacles, further enhancing the performance of the wireless power transfer (WPC) system. Finally, after collecting energy, the terminal node repeatedly transmits a short reference signal composed of multiple chaotic sequences using the short reference technique to improve energy efficiency and transmission rate. Both the ES and D sides employ a repeated transmission method to adjust the energy coefficient and short reference coefficient, respectively. Although their functions differ, their structures are consistent and simple. Simulations and numerical calculations verify that, compared to existing RIS-assisted DCSK-WPC models, the proposed model improves overall transmission efficiency and saves energy without compromising the bit error rate.