基于多模谐振器的高温超导多通带滤波器研究

发布时间：2018-04-24 22:42

本文选题：高温超导 + 多通带滤波器　；参考：《清华大学》2016年博士论文

【摘要】：滤波器用于抑制带外干扰信号,是决定无线通信系统与探测系统带外抗干扰能力和灵敏度的关键部件。随着现代通信技术的不断发展,通信设备朝着多频化、集成化和紧凑化的方向不断前行,迫切需要具有多个工作频带的多通带滤波器。采用多模型谐振器设计的滤波器具有更加紧凑的结构,更低的损耗和噪声。受常规电路材料损耗和设计方法的限制,基于多模谐振器设计的多通带滤波器普遍存在节数较低、损耗较大的问题。利用高温超导材料微波损耗极低的优异特性,可实现插入损耗小、带边陡峭、带外抑制度高的高性能带通滤波器。因此,集合多通带工程应用需求、超导滤波器和多模谐振器性能优点的高温超导多通带滤波器具有重要的学术研究意义和工程应用价值。本论文针对基于多模谐振设计多通带滤波器的难点进行了研究,并提出了相关解决方案:(1)提出一种基于S21群时延特性的多模谐振器外部品质因数Qe提取方法,解决了多模谐振器因多个谐振模式的频率特性互相影响,导致外部品质因数Qe提取困难的问题。提出一种优化设计方法,根据所要设计的滤波器技术参数推导得到所需的谐振频率,并最终计算出五模谐振器的结构初值,避免了盲目调节,提高了设计效率。利用以上方法用一个五模谐振器设计并制作了双通带滤波器,制作后的测试结果性能优异。(2)提出了一种新型的三模嵌入式枝节线加载谐振器结构和容性负载平行耦合线方法,解决了三模谐振器在三个谐振频率处同时满足相同耦合系数的难题。提出了一种双馈线搭接的外部耦合结构,提高了滤波器制作的稳定性、降低滤波器损耗,制作出了性能优异、结构紧凑的高温超导三通带滤波器。(3)构建了一种易于调节频率的枝节线加载的四模谐振器,采用电耦合和磁耦合分离的方法,使得各个模式的耦合系数可独立控制、调节。提出了2个搭接馈线和2个耦合馈线的四馈线外部耦合结构,解决了各个模式外部耦合的独立可控的问题。设计并制作了性能优异、结构紧凑的高温超导四通带滤波器。最终解决了采用四模谐振器设计中心频率和带宽独立可控的四通带滤波器的难题。
[Abstract]:The filter is used to suppress the out-of-band interference signal and is the key component to determine the anti-jamming ability and sensitivity of the wireless communication system and the detection system. With the development of modern communication technology, the communication equipment is moving forward in the direction of multi-frequency, integration and compactness. It is urgent to have multi-band filter with multiple working bands. The filter designed with multi-model resonator has more compact structure, lower loss and lower noise. Due to the limitation of conventional circuit material loss and design method, the multipass filter based on multi-mode resonator generally has the problem of low number of nodes and large loss. The high performance bandpass filter with low insertion loss, steep band edge and high outband suppression can be realized by using the excellent characteristics of high temperature superconducting material with extremely low microwave loss. Therefore, high temperature superconducting multiband filters with the advantages of superconducting filters and multi-mode resonators have important academic significance and engineering application value. In this paper, the difficulty of designing multipass band filter based on multimode resonance is studied, and the related solution: 1) A method of extracting external quality factor Qe of multimode resonator based on S21 group delay characteristic is proposed. The problem of external quality factor Qe extraction due to the influence of frequency characteristics of multiple resonant modes on multimode resonators is solved. An optimal design method is proposed to derive the required resonant frequency according to the technical parameters of the filter to be designed. Finally, the structure initial value of the five-mode resonator is calculated, which avoids the blind adjustment and improves the design efficiency. Using the above method, a two-pass band filter is designed and fabricated with a five-mode resonator, and the test results are excellent. A novel three-mode embedded side-line loaded resonator structure and capacitive load parallel coupling line method is proposed. The problem of three-mode resonator satisfying the same coupling coefficient at three resonant frequencies is solved. In this paper, an external coupling structure of doubly-fed lapping is proposed, which improves the stability of filter fabrication, reduces the filter loss, and makes the filter with excellent performance. A four-mode resonator, which is easy to adjust the frequency and loaded by a branch line, is constructed. The coupling coefficient of each mode can be independently controlled and adjusted by using the method of electric coupling and magnetic coupling separation. The external coupling structure of four feeders with two overlapped feeders and two coupling feeders is proposed, which solves the problem of independent and controllable external coupling of each mode. A high temperature superconducting four pass band filter with excellent performance and compact structure is designed and fabricated. Finally, the four-mode resonator is used to design a four-pass filter with independent and controllable center frequency and bandwidth.
【学位授予单位】：清华大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TN713

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