Design of dual-band RF energy collection system in environment

This paper proposed an environmental RF energy acquisition system based on GSM-1800 and WiFi frequency bands. The system consists of a dual-frequency circularly polarized antenna, a dual-frequency rectifier circuit and a load. The impedance bandwidth of the circular polarization antenna is 1 GHz～2.6 GHz, and the axial ratio bandwidth is 1.78 GHz～1.96 GHz and 2.37 GHz～2.59 GHz. The designed dual-frequency rectifier has a maximum RF-DC efficiency of 44% when the 1.825 GHz single-frequency input is 10 dBm. In the case of 2.45 GHz input power of 8 dBm, the highest RF-DC efficiency is 49%. When the dual-frequency input power is 7.5 dBm, the maximum RF-DC conversion efficiency is 53% and the DC voltage is 1.73 V. Placing the designed dual-band energy harvesting system near the router and the phone being called, an LED light can be lit to realize its energy harvesting function.