RIS-Assisted Near-Field Integrated Sensing and Wireless Power Transfer Systems

Integrated radar sensing and wireless power transfer (ISWPT) is a recently proposed technique that aims to achieve the dual functionalities of radar sensing and wireless power transfer (WPT) using the same hardware platform. In this paper, we investigate an ISWPT system assisted by reconfigurable intelligent surfaces (RIS), where energy receivers are positioned within the near-field region of the RIS. For such a scenario, we study the joint optimization of beamforming at the base station (BS) and the reflection phase of the RIS to enhance the performance of WPT and radar sensing. The formulated problem, though non-convex in nature, is efficiently addressed through the introduction of an alternating optimization algorithm. Numerical results validate the effectiveness of our proposed solutions, underscoring their superiority in terms of both radar sensing and wireless power transfer performance compared to baseline schemes.