A Broadband Dual-Polarized Radio Frequency Energy Harvesting Antenna Array

This paper proposes and designs a dual-element radio frequency (RF) energy harvesting antenna array with high bandwidth and ±45° cross-polarization, operating in the 1.7GHz - 2.7GHz frequency band. The rectenna is about Llflmmxoumm in size and shows good applicability for self-waking-up and energy supply of nodes in wireless sensor networks. The element of the dual-polarized antenna array can achieve a gain of 7.66dB at the center frequency of 2.2GHz, and the dual-element array can reach a gain of 10.83dB at 2.2GHz. Verified rigorously, the antenna array has strong directivity with an actual gain of around 10dB in the gain direction. When paired with a rectifier, the measured open-circuit voltage can reach about 2.75V. Besides, the array rectenna has an effective receiving distance of up to around 12m for RF energy. Even at a distance of 12.22m from the RF transmitting source, its open-circuit voltage remains as high as 0.62V, thus meeting the self-powering and self-waking-up requirements of wireless sensor nodes well.