Miniaturization And Application Of Microstrip Open-loop Resonator Loaded With Fragments

Miniaturized circuit structures are required in modern RF/microwave systems.Res-onators are common components in RF/microwave circuits,whose miniaturized design has been continuously and widely concerned.Loading technology of resonator is a rep-resentative technology of miniaturized design,and the loading manners are flexible and varied.According to the needs of the design of microstrip structure and chipless RFID tag,fragment-type loading of miniaturized microstrip resonant ring and its applications in microstrip filter and chipless RFID tag are emphatically researched in this thesis.The main jobs of this thesis are as followed:1)Fragment-type loading structure is systematically carried out.Firstly,fragment-type loading design model of resonant ring and the design framework based on MOEA/D-GO optimization are established.Then,different optimization ob-jective functions are discussed to meet the design needs of microstrip filter and passive RFID chip.Finally,the optimal fragment-type loading design is carried out.A planar loading microstrip open resonant ring smaller than other counter-parts is given.2)The research of microstrip filter based on miniaturized fragment-type loading mi-crostrip resonant ring is carried out.Firstly,a miniaturized open resonant ring is designed by selecting appropriate objective functions.And a filter based on the open resonator ring is also designed.Then,positions of the transmission zeros of the filter are adjusted to improve the selectivity of the filter via loading coupling line.Finally,the filter was fabricated and tested to verify the effectiveness of the design.3)A chipless RFID tag based on miniaturized fragment-type loading microstrip res-onant ring is designed.Firstly,a single-mode miniaturized high-Q fragment-type loading resonator ring is designed by selecting appropriate objective functions.Then,based on the structure above,a dual-mode chipless tag with large informa-tion capacity which is easy to detect is designed.Finally,the tag was fabricated and tested to verify the feasibility of the design.4)Based on the miniaturized fragment-type loading microstrip resonant ring,the coding technology of chipless RFID tags is investegated.According to the cur-rent distribution of the tag,the loading cells were distinguished to different cate-gories.A chipless tag encoding multi-bit data was obtained by removing different categories cells which can realize the resonant frequency shift.Furthermore,tags were fabricated and tested to verify the effectiveness of the coding scheme.