负群时延滤波器的设计与研究

发布时间：2018-10-22 10:01

【摘要】：随着微波射频通信的快速发展,传输系统对相位和信号失真度等性能的要求逐渐提高,负群时延滤波器因其特殊的性能受到越来越多的关注。但是目前为止尚未形成关于负群时延滤波器的设计理论,且针对纯微带负群时延滤波器的相关研究成果较少,特别是可调的负群时延滤波器。本文在传统带通滤波器的综合方法的基础上,提出了负群时延滤波器的基于有损滤波器和带阻滤波器的两种方案的新型综合方法,并以此为基础分析和研究了负群时延滤波器的设计理论。在理论研究的基础上,本文设计了两款负群时延滤波器,分别可实现固定负群时延滤波器及单/双频段可调负群时延滤波器。本文首先提出一种采用电耦合方式耦合的新型开环谐振器结构,并利用此结构设计一款固定负群时延滤波器,并通过输入/输出阻抗匹配改善了滤波器的损耗特性。实测结果表明,该滤波器中心频率为2.149 GHz,所能实现的负群时延为-15.22 ns,插入损耗小于27.43 dB。与相关研究相比,该滤波器能够在衰减较小的情况下实现较大的负群时延。在固定负群时延滤波器设计的基础上,本文利用微带线和短路耦合线设计了单/双频段可调的负群时延滤波器,所设计的可调滤波器具有灵活的调谐性,可以实现独立可调的中心频率和负群时延,也可同时对所有参数进行调节。单频段可调滤波器能够实现的中心频率和负群时延的最大调节范围分别为1.450~1.870 GHz和-2~-30 ns,双频段可调滤波器的中心频率分别在1.435~1.855 GHz和2.395~2.695 GHz范围内可调,负群时延最大可调范围分别是-4~-22 ns和-4~-32 ns。实测结果均与仿真结果高度吻合,与相关研究成果相比,所设计的可调滤波器插入损耗更小且具有更宽的可调范围。
[Abstract]:With the rapid development of microwave radio frequency communication, the requirement of phase and signal distortion in transmission system has been improved gradually. The negative group delay filter has attracted more and more attention because of its special performance. However, there is no design theory on negative group delay filters, and there are few researches on pure microstrip negative group delay filters, especially tunable negative group delay filters. Based on the traditional synthesis method of bandpass filter, this paper presents a new synthesis method of negative group delay filter based on lossy filter and bandstop filter. Based on this, the design theory of negative group delay filter is analyzed and studied. On the basis of theoretical research, two negative group delay filters are designed, which can realize fixed negative group delay filters and adjustable negative group delay filters in single / double frequency band respectively. In this paper, a novel open-loop resonator structure with electrically coupled coupling is proposed, and a fixed negative group delay filter is designed using this structure. The loss characteristics of the filter are improved by the input / output impedance matching. The experimental results show that the negative group delay of the filter with a central frequency of 2.149 GHz, is -15.22 ns, and the insertion loss is less than 27.43 dB.. Compared with the related research, the filter can achieve a large negative group delay in the case of less attenuation. Based on the design of fixed negative group delay filter, a single / double band tunable negative group delay filter is designed by using microstrip line and short circuit coupling line. The tunable filter is flexible and tunable. It can realize independent adjustable center frequency and negative group delay, and can also adjust all parameters at the same time. The maximum adjustable range of the center frequency and negative group delay of single frequency tunable filter is 1.450V 1.870 GHz and -2um -30 ns, respectively. The center frequency of the tunable filter is adjustable in the range of 1.435 ~ 1.855 GHz and 2.395n / 2.695 GHz, respectively. The maximum tunable range of negative group delay is -4 ~ 22 ns and -4 ~ 32 ns., respectively. The measured results are in good agreement with the simulation results. Compared with the related research results, the insertion loss of the designed tunable filter is smaller and has a wider adjustable range.
【学位授予单位】：杭州电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN713

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