Printed circularly polarized spilt ring resonator monopole antenna for energy harvesting
Dalia N. Elshaekh, Hesham A. Mohamed, Heba Shawkey, Somaya Kayed
Abstract
The growing development of inter-networking devices and internet-of-things (IoT) are required to make use of all possible energy sources for different types of sensor. Ambient renewable energy resources are needed and received more attention this era especially those present at all the day and not depend on moving, wind or sunlight. The ambient electromagnetic field as radio frequency (RF) is constantly present, even with a very small amplitude, a reliable alternative to supply the system with a low power rate. This paper presented a split ring resonator shaped monopole antenna circularly polarized to resonate at different resonant on low cost FR4 substrate size of Universal Serial Bus (USB) integrated with multiband rectifier circuit by using high frequency structure simulator (HFSS) ver. 15. The proposed antenna is circularly polarized could be used at any orientation to be used as portable RF energy harvesting device with dimensions 15 × 35 mm2. The −10 dB impedance matching bandwidth of the proposed monopole antenna start to resonate from 2 GHz up to 10 GHz with band notches extended from 2.5 GHz to 3.5 GHz, hence the antenna resonates at most of wireless communication. In addition, the single stage of voltage doubler rectifier (VDR) is added and designed to convert the RF into direct current (DC) signal with wideband of operation extended from 2 GHz up to 10 GHz with overall size of the rectifier is 9.2 × 20 mm2. A pair package of SMS 7630 Schottky diode is used with a voltage drop of 0.34 V. The matching circuit is optimized using Advanced Design System (ADS) simulation tool such for maximum DC output signal through the frequency band of operation. The maximum DC output voltage is 0.94 V for 5 kΩ load resistance with 60% power conversion efficiency at −5 dBm input signal.