Self-Diplexing Shared-Aperture Omnidirectional Rectenna for Simultaneous Wireless Information and Power Transfer (SWIPT)

This letter proposes a self-diplexing shared-aperture (SA) omnidirectional rectenna for simultaneous wireless information and power transfer (SWIPT). Unlike the traditional frequency splitting (FS) methods, this approach reuses the same antenna aperture to achieve omnidirectional reception and separation of power and communication signals at different frequencies, thereby enhancing system integration and environmental adaptability. The antenna is designed using characteristic mode analysis (CMA), with a monopole mode at low-frequency (LF) and a quasi-monopole mode excited by an equal-amplitude in-phase feeding network at high-frequency (HF), achieving omnidirectional radiation with vertical polarization (VP) at both bands. Additionally, a low-power rectifier is designed and verified, and a practical SWIPT system is constructed for testing, where the HF signal is used for communication and the LF signal for RF energy harvesting (REH). The results demonstrate that the designed rectenna and architecture are suitable for SWIPT applications.