A Dual-Band Dual-Polarized Antenna for Harvesting in Cellular and Digital Terrestrial Television Bands

The growing prevalence of IoT devices has heightened the focus on minimizing energy consumption in low-power electronic systems. Ambient radio frequency (RF) energy harvesting allows self-sustaining electronic devices to operate in IoT networks without cables, batteries, or allocated energy sources. This paper presents an innovative printed dual-band dual-polarized antenna designed for ambient RF energy harvesting in IoT applications. The proposed antenna targets efficient RF energy conversion from the most prevalent cellular frequency bands (sub-1 GHz and 1800 MHz) and sub-700 MHz Digital Terrestrial Television. This antenna is a significant advancement in the field, boasting a wide circularly polarized 610-968 MHz bandwidth and a linearly polarized bandwidth covering the GSM/4G 1800 MHz band. The antenna's integration with a rectifier circuit demonstrates its ability to convert ambient RF energy into electrical power, regardless of the source antenna orientation. This integrated antenna development significantly reduces battery dependency in low-power IoT devices, paving the way for more sustainable and versatile wireless networks. Specifically, this antenna is crafted to achieve broad CP and adequate impedance bandwidths across targeted frequencies, crucial for the diverse requirements of ambient RF energy harvesting. Such a design meets our primary objectives of capturing RF energy effectively, with its omnidirectional pattern enabling it to collect ambient RF signals from different polarizations and directions.