高温超导滤波器具有极低的插入损耗、极高的带边陡峭度和带外抑制，应用于移动通信、雷达探测等领域可以提高系统灵敏度，减小带外干扰。这些应用领域的飞速发展，对滤波器的性能提出了更高的要求。近年来，低频超导滤波器如何有效抑制寄生通带从而实现宽阻带响应已成为新的研究热点。同时，跳频通信、信道化接收等技术的发展以及特殊通信装备可靠性小型化的要求，使超导滤波器多通道集成的重要性日益凸显出来。本论文研究了低频高温超导滤波器宽阻带响应的实现方法。通过建模仿真研究了不同接地条件对四分之一波长滤波器性能的影响，确定最佳接地模式。据此研制了P波段滤波器，将第一寄生通带推远到三倍频位置。论文还提出了以交错谐频谐振器来构建宽阻带滤波器的方法，深入分析了级联式和耦合式交错谐频滤波器的滤波特性。论文研制了相对带宽为0.2%的宽阻带超导滤波器，在五倍频甚至更宽的范围内有效抑制了寄生模式，实现了滤波器的宽阻带响应，验证了交错谐频设计思想的有效性。提出低频超窄带多通道滤波器集成方案。采用了末节谐振器修正的分支效应补偿方法与基片切缝和电磁屏蔽的通道去耦方法，解决了多通道滤波器集成时带内失配和通道之间耦合串扰的问题。设计了VHF波段超窄带双通道集成滤波器，测试表明这两个滤波器同时具有优异的频率响应特性，通带内反射损耗达到-17 dB，通道间隔离度达到-76 dB。双通道同时精确对准所需的中心频率，偏差小于万分之一。在综合考虑灵敏度指标与线性度指标的基础上，设计二级放大及增益分配方案。据此成功研制了超导接收机射频前端，测试表现了优异的性能。研究比较了低频超窄带微波探测系统中常规前端与超导前端的抗干扰性能，设计试验方案，进行了超窄带超导接收机应用于特殊微波探测系统的现场试验，极大地改善了原探测系统的抗干扰能力。论文在小型化宽阻带滤波器设计和多通道集成等方面的研究具有重要的学术意义和工程价值。

High temperature superconducting (HTS) filters exhibit excellent performances such as extremely low insertion loss, steep band-edges, and high out-of-band rejection. They have been widely used in mobile communications, satellite communications, radar detection, and radio astronomy. With the rapid development of mobile communications, more demands have been placed on high-performance HTS filters. Bandpass filters with wide stopband performance have attracted more interests. Moreover, multi-channel integration of ultra-narrowband HTS filters is of more and more importance.In this dissertation, two methods in realizing HTS filters with wide stopband performance are investigated. A narrowband HTS filter with a 3%-bandwidth at P-band has been successfully designed with quarter-wavelength resonators. The effect of the grounding method of the quarter-wavelength resonators on the filter response is simulated and addressed. The measured results of the narrowband HTS filter show good performances with the first spurious passband located at about 3f0.HTS filters using resonators with different harmonic frequencies are proposed to suppress harmonic responses and realize wide stopband performance. Two filter topologies, cascaded and coupling ones, are utilized. An ultra-narrowband HTS filter with a 0.2%-bandwidth at VHF-band has been successfully designed based on this method. Measured results show good performance and validate the proposed method.The multi-channel HTS filters are studied by the means of equivalent circuit analysis, EM simulations and experiments. A four-channel HTS receiver is designed and fabricated. Measured results show high performance with both high return loss and high isolation in both channels. The filters are accurately tuned to the desired center frequencies with a deviation of less than 0.01%. These studies are of great academic significance and engineering importance in developing high-performance HTS filters with wide stopband response and in the integration of multi-channel filters.