Research And Design Of Rectifier Circuit Based On Impedance Compression Network

With the development of the Internet of Things,its power supply problem has become a bottleneck and restrict its development.RF energy harvesting can provide energy for micro-power chips and effectively solve the power supply problem in the Internet of Things.As a key part of RF energy collection,rectifier circuit and its matching network has become one of the research hotspots in related fields.According to the requirements of the scientific research projects,In this thesis,rectifier circuit based on the a single-branch resistance compression network and a broadband resistance compression network is researched.The details are as follows:1)A transmission line based single-branch resistance compression network(SRCN)has been proposed to reduce the sensitivity of input impedance of rectifier to input power.It consists of a shorted-stub and an opened-stub,the total length of the shorted-and opened-stub is ?/8.Then,a rectifier operating at 2.4 GHz is designed based on SRCN,and the radio frequency(RF)-DC conversion efficiency of the rectifier is simulated.The results indicate,the proposed SRCN can effectively reduce the variation range of input impedance which changes with input power levels.As a result,the RF-DC conversion efficiency have a promotion of 8%-15% in the input power range of 0-20 d Bm.By simplifying the rectifying circuit into a single-branch structure,the proposed SRCN has achieves a simpler circuit structure and lower cost.2)A transmission line based wideband resistance compression network(WRCN)has been proposed.It is proved that it can achieve resistance compression in a wide frequency range,and the compression ratio can be as low as 1.87:1.Then,a rectifier based on the WRCN is designed.The measured results show that efficiency of rectifier from 3.3 GHz to 5.2 GHz is better than 40% in case that input power is 10 d Bm.Also,when the load resistance changes in the range of 300-5000 ?,it is also larger than 30%.