高温超导线性相位滤波器的研制

【作者】 张天良；

【导师】 罗正祥；

【作者基本信息】 电子科技大学 ， 物理电子学， 2004， 硕士

【摘要】 与利用波导腔、介质谐振器和常规金属平面结构设计的滤波器相比，利用高温超导（HTSC）薄膜研制的微波滤波器具有体积小、重量轻、插损小、Q值高和选频特性好等优点。本文首先介绍了高温超导材料的基本特性、对高温超导滤波器的应用进行了简单分析、介绍了线性相位滤波器的设计原理，然后采用全波电磁仿真方法，利用CAD工具，建立了高温超导滤波器的理论仿真模型，综合设计符合要求的高温超导线性相位滤波器，并进行了器件的制作、封装和测量。本文解决了高温超导微波无源器件的设计、光刻工艺、密封封装和低温测量等难点后，成功地在LaAlO3基片上设计并制作了中心频率为1.75GHz，带宽为80MHz，带内插损<0.2dB，带内群时延波动（线性相位特性）<2ns，带外抑制>25dB的高温超导薄膜微带结构的线性相位滤波器，测试结果显示所制作的高温超导线性相位滤波器其带内插损最好可达到0.141dB，带外抑制>20dB,基本满足设计要求。关于高温超导线性相位滤波器的研制国内还未见到相关报道。更多还原

【Abstract】 The microwave filters using HTSC (high temperature superconductivity) thin filmshave the advantages of low resistance and high quality factor, so their performances aremuch better than the filters using wave-guide, dielectric resonance or conventionalmetal planar structures.This thesis presents the characteristics of HTSC materials and analyzes the using ofHTSC filters firstly, and then also introduces the theory of HTSC linear phase filters.The modes of HTSC resonance and filters have been built using CAD programs byfull-wave field simulators. Then a HTSC filter according to the aim of designs has beensynthesized, manufactured, installed and measured. In this paper, difficulties such as thedesign of HTSC microwave passive component, the lithography process technology, theencapsulation and the measurement in low temperature and so on have been solved.With a special transfer function changed from a six-pole quasi-elliptic function byextracted pole, on YBCO/LaAlO3/YBCO substrate, a HTSC filter having a bandwidth of80MHz, which center frequencies is1.75GHz, the insertion loss is less than0.2dB andthe group delay fluctuation is less than2ns，has been designed, and measurement resultssatisfied the requires of designs. There is no report about HTSC linear phase filters inour country now.更多还原