Abstract—Recently, Reconfigurable Intelligent Surfaces (RIS) have gained significant attention from both academia and industry due to their attractive features such as passive beamforming, energy efficiency, and cost-effectiveness. In this paper, we consider a system where an RIS is deployed to support data transmission from an Information Transmitter (ITx) to an intended Information User (IU) and power transfer from a Power Transmitter (PTx) to a Power User (PU). Due to the high power required for power transfer, excessive leakage from the PTx can damage sensitive components in the IU. To mitigate this interference, we propose an efficient optimization method based on the bat algorithm that optimizes the reflection phase coefficients of the RIS. Our simulation results demonstrate that the proposed approach can suppress interference from the PTx to around –15 dB and enhance the IU’s Signal-to-Interference Ratio (SIR) by up to 52 dB compared to baseline methods. Furthermore, a detailed comparison with Accelerated Particle Swarm Optimization (APSO) shows that while APSO maintains a stable PU power of approximately 31.7 dB and a low IU SIR (< 4 dB), our method balances power transfer and interference suppression by achieving a PU power of approximately 26.2 dB and an IU SIR in the range of 38–44.8 dB after 100 iterations. Additional analyses reveal that higher RIS resolution further improves the SIR and that the approach remains robust under varying user positions. These quantitative results underscore the effectiveness and robustness of our bat algorithm-based optimization method for RIS-assisted simultaneous wireless information and power transfer systems.

Keywords—interference suppression, reconfigurable intelligent surface, simultaneous wireless information and power transfer, bat algorithm


Cite: L. V. Thai, N. V. Cuong, T. V. Luyen, and N. M. Tran, “Interference Suppression Enabled by Reconfigurable Intelligent Surface for Simultaneous Wireless Information and Power Transfer Applications," Journal of Communications, vol. 20, no. 2, pp. 184-198, 2025.


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