摘要随着无线通信技术的迅速发展和广泛应用，无线通信设备的高性能、小型化、低成本、易于设计等优点受到了越来越广泛的关注。低通滤波器是无线通信系统的重要组成部分之一，其性能的优劣很大程度上决定了通信系统的工作性能。本文研究了谐振器的小型化技术。我们对三角形谐振器、梯形谐振器的谐振特性进行了理论分析，通过分析得出了谐振器小型化的一般性思路。根据谐振器的小型化技术，本文提出了微带低通滤波器高性能、小型化的设计方案，并利用这种方案设计出了高性能小型化的微带低通滤波器。 61125

    本文对阶梯阻抗三角形基片谐振器和阶梯阻抗梯形基片谐振器的性能进行了研究，利用加载三角形基片谐振器和梯形基片谐振器设计一个小尺寸和宽阻带的微带低通滤波器。折叠线的使用能进一步减小低通滤波器的电路尺寸。

      本论文的研究成果在无线通信系统电路设计中具有重要的应用价值。

毕业论文关键词: 小型化，高性能，低通滤波器，微带线，梯形谐振器，三角形谐振器，超宽带

毕业设计说明书（论文）外文摘要

Title  Compact wide-stopband  microstrip lowpass filter 

Abstract With the development and wide application of the wireless communication technology, the design of filter with high performance, compact size, low cost, and design flexibility has drawn more and more attention. Lowpass filter takes a key role in the wireless communication system, and its performance determines the quality of communication system. Miniaturization technologies of resonators were studied in this thesis. The resonance properties of triangular resonator, and trapezoid resonator were theoretically analyzed respectively. According to the detailed theory analyzing, general ideas of resonator miniaturization were proposed. With these ideas, a scheme for microstrip lowpass filter design with high performance and compact size is presented. Based on this scheme, one lowpass filter with high performance and compact size have been designed. In this article，some research on the performance of stepped-impedance triangular patch resonatorsare done in this dissertation. To achieve compact size and ultra-wide band rejection, both triangular patch resonators and radial patch resonators are introduced in the filter. To further reduce the circuit size of the filter, the meander transmission lines are also adopted in the design. 

furthermore, it also has an important application value in the RF front-end circuit design of wireless communication system.

Keywords: Compact, high performance, lowpass filter, microstrip, trapezoid resonator, triangular resonator,  ultra-wide band 

1 绪论 5

1.1 课题背景——微带低通滤波器的重要性及特性概述 5

1.1.1 特性要求一 ——高性能 5

1.1.2 特性要求二 ——小型化 5

1.1.3 目前所面临的难点 5

1.2  国内外研究的现状 6

1.2.1 新型封装技术MCM的应用 6

1.3  本文主要内容 12

2 微带传输线与滤波器及微波网络的基本理论 13

2.1 微带传输线的基本理论 13

2.1.1 微带线的基本概念 13

2.1.2 微带的特性阻抗 14

2.1.3 微带的衰减和Q值