High Efficiency RF-DC Rectifier Based On GaN Transistor

The development of microwave wireless energy transmission technology puts higher and higher requirements on RF-DC rectifiers.The rectification efficiency of the rectifier becomes the key to restrict the energy transmission efficiency of the entire system.The third-generation semiconductor material GaN,with its excellent electrical characteristics,makes GaN HEMT an ideal rectifier device,and the research of GaN-based RF-DC rectifiers has gradually become a hot spot.The main work of this article consists of the following four points:(1)At first the EEHEMT model is used to perform parameter extraction and modeling for the second-generation high-voltage GaN HEMT of CREE company model CG2H40010,which makes up in the blank of the corresponding device model.After simulating the obtained model,the I-V characteristic curve fits the measured data well,and the error is within 5%.(2)Based on the model of CG2H40010 established in the first step,a power amplifier working at 2.8 GHz was designed with a power added efficiency(PAE)of75%,and a high-efficiency RF-DC rectifier at 2.8 GHz was obtained according to the principle of reverse time duality,whose rectification efficiency is 72.3%.(3)Then,to solve the problem of narrow band existing in the research,a broadband self-synchronous rectifier was designed with a bandwidth more than 300 MHz and a maximum rectification efficiency up to 85%.(4)Finally,in order to overcome the shortcomings that the bandwidth of the self-synchronous rectifier is difficult to be further improved,the concept of reconfigurable circuit is adopted.A series of grounding capacitors are added to the coupling loop of the self-synchronous rectifier to design a reconfigurable broadband rectifier.The operating bandwidth can be switched according to the input,which makes the final obtained bandwidth is greater than 400 MHz.