An Optimized Rectifier Design for RF Energy Harvesting at the 2.45 GHz WiFi Frequency Band

Radio frequency-based energy harvesting is a promising technique for the communications society. This technology still faces some technical challenges to power up modern micro-devices. These devices need a constant power source to enable these devices to work properly. In this investigation, the amount of the harvested DC power from radio frequency waves was considered. This work proposed a simple design having a small size with an improved harvested power level. The advanced design system simulation software was utilized by using the harmonic balance controller. The proposed design was adjusted to harvest radio waves of the 2.45 GHz frequency band. The design passed through three steps included the unmatched single-stage voltage multiplier circuit, the matched single-stage voltage multiplier circuit, and the optimized voltage multiplier circuit. Results showed that the maximum conversion efIiciency was 66% for the optimized circuit at the input power level of 7 dBm. The conversion range of the applied input power was between -25dBm to +20dBm. This circuit achieved the top harvested DC power of 12.34 mW at the applied power of 20 dBm at the load of 1 KΩ with output voltage and current values of 3.51 V and 3.51 mA respectively.