Octa-Port Dual-Polarized Antenna/Rectenna for MIMO Simultaneous Wireless Information and Power Transfer (SWIPT)

Wireless sensor networks face a challenge with the limited battery capacity in IoT sensor nodes and low communication quality, hindering network sustainability and increasing maintenance costs. To simultaneously address these issues, a novel octa-port antenna/rectenna with dual-polarization capabilities is proposed for simultaneous wireless information and power transfer (SWIPT) operation. The four ports of the design realize a rectenna for wireless power transfer (WPT), and the other four ports are dedicated to MIMO operation for wireless information transfer (WIT). The rectenna has a gain of 7.2 dBi with a dc beamwidth of 72.2°. The rectenna achieves a good PCE of 50.92% at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1700~\Omega $ </tex-math></inline-formula>, translating to a dc power harvesting capacity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$72.47~\mu $ </tex-math></inline-formula> W at −8.46-dBm RF input power. The MIMO antennas maintain a bandwidth of 200 MHz, with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$S_{11}$ </tex-math></inline-formula> less than −10 dB centered around 5.8 GHz. The mutual coupling between co-polarized antenna/rectenna ports and among the MIMO antenna ports is less than −12 and −25 dB, respectively.