# High-Efficiency Triple-Band RF-to-DC Rectifier Primary Design for RF Energy-Harvesting Systems  
[PERSON]  
1 School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; [EMAIL_ADDRESS] (C.K.V. ); [EMAIL_ADDRESS] (J.N.S. ); [EMAIL_ADDRESS] (S.N. ); [EMAIL_ADDRESS] (S.K.G.) [PERSON]  
1 School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; [EMAIL_ADDRESS] (C.K.V. ); [EMAIL_ADDRESS] (J.N.S. ); [EMAIL_ADDRESS] (S.N. ); [EMAIL_ADDRESS] (S.K.G.) [PERSON]  
1 School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; [EMAIL_ADDRESS] (C.K.V. ); [EMAIL_ADDRESS] (J.N.S. ); [EMAIL_ADDRESS] (S.N. ); [EMAIL_ADDRESS] (S.K.G.) [PERSON]  
1 School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; [EMAIL_ADDRESS] (C.K.V. ); [EMAIL_ADDRESS] (J.N.S. ); [EMAIL_ADDRESS] (S.N. ); [EMAIL_ADDRESS] (S.K.G.) 2  
[PERSON]  
1 School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; [EMAIL_ADDRESS] (C.K.V. ); [EMAIL_ADDRESS] (J.N.S. ); [EMAIL_ADDRESS] (S.N. ); [EMAIL_ADDRESS] (S.K.G.) 2  
[PERSON]  
1 School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; [EMAIL_ADDRESS] (C.K.V. ); [EMAIL_ADDRESS] (J.N.S. ); [EMAIL_ADDRESS] (S.N. ); [EMAIL_ADDRESS] (S.K.G.) 2  
input power of 10 dBm, at 2.45 GHz and 5.80 GHz, respectively. In 2017 [10], [PERSON] et al. introduced a dual-band rectifier in the GSM-900 and GSM-1800 bands. The rectifier topology was based on a Latour doubler. The efficiency obtained was greater than 30% at 942 MHz and greater than 20% at 1805 MHz for an input power greater than \(-\)10 dBm and an output load equal to 15 kOhm. In 2018 [11], a voltage-doubler circuit as a rectifier was introduced, which consisted of two Avago HSMS2850 Schottky diodes and two capacitors. The results demonstrated that the RF-to-DC maximum efficiency was 63% at 1.95 GHz and 69% at 2.50 GHz, for an input power of 7.0 dBm and 3.5 dBm, respectively, and a resistive load of 1.0 kOhm. In 2019, [PERSON] et al. [12] utilized a \(\lambda/4\) T-junction power divider to connect two branches of a rectifier, to extend the range of input power of the system with high conversion efficiency. They applied their proposed technique to both single- and dual-band rectifiers. They reported a measured peak efficiency of 68% for the single-band rectifier (915 MHz) and an input power range from \(-\)5 dBm to 31 dBm by setting an efficiency threshold of more than 70% of its peak efficiency of 66% for an input power range from \(-\)6 dBm to 33 dBm (efficiency threshold greater than 70%) at 915 MHz and a peak efficiency of 58% for an input power range from 10 dBm to 32 dBm (efficiency threshold greater than 70%) at 2.45 GHz. In 2020 [13], a system was proposed that resonated in the frequency bands of 4G (2.67 GHz) and 5G (3.591 GHz) mobile communication systems. Numerical results demonstrated that the RF-to-DC maximum efficiency was 56.11% at 2.67 GHz and 57.95% at 3.591 GHz, for an input power of 6.0 dBm and a resistive load of 2.0 kOhm. The same year, [PERSON] et al. [14] introduced a rectenna system for precision agriculture. The two-stage rectifier circuit was based on the Greinacher voltage-doubler and operated in the LoRaWAN (863 MHz-870 MHz) and EGSM-900 (925 MHz-960 MHz) mobile communication frequency bands. The maximum simulated and measured efficiency of 75% and 73.6% were achieved for input power \(P_{in}=2\) dBm and 4.8 dBm, respectively, for an output load equal to 7 kOhm. The ever-increasing demand for more energy, as well as the remarkable augmentation of ambient RF energy sources led the scientific community to consider triple-band rectifiers as an efficient technique to harvest even more power. In 2016 [15], a triple-band differential rectifier using a single-stage Villard topology was designed. They used microstrip lines to implement an impedance-matching network and achieved a maximum efficiency of 42% for an input power of 14 dBm.