Study of the Circularly Polarized Rectennas for UHF Bands Wireless Power Transmission Applications

• Main Authors: Ren-Hao Chen, 陳仁浩
• Other Authors: 孫卓勳
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/cz9244

碩士 === 國立臺北科技大學 === 電腦與通訊研究所 === 97 === In this thesis, the circularly polarized rectennas for Ultra High Frequency (UHF) bands (925 MHz and 2.45 GHz) wireless power transmission applications have been designed and studied. This study includes: 1. Design of a circularly polarized wide-slot antenna which can reduce the multi-path fading efficiently and solve the depolarization effect of random polarization in free space and complicate environment. 2. Design of the filter and matching network by using the chip components. It can not only achieve the impedance matching between the receiver antenna and voltage-doubler rectifier, but also suppress the higher order harmonics efficiently. 3. Design of the voltage-doubler rectifying circuit. A RF schottky barrier diode suitable for the current specification and the requirement for design of the voltage-doubler rectifying circuit is selected as a rectifying device of the circuit to increase the output DC voltage and RF-to-DC conversion efficiency. A circularly polarized wide-slot antenna and a rectifying circuit for UHF bands wireless power transmission system applications not only based on the measurement and simulation, but also compare with the parameters and characteristics in literature. Our study showed that the designed circularly polarized rectenna for UHF bands wireless power transmission which not only has higher output DC voltage and greater RF-to-DC conversion efficiency with power detection sensitivity reaching as low as -14 dBm, but also exhibits up to 65% size reduction over the conventional design.