Compact Low-Pass Filter with Sharp Skirt Characteristics and Broad Stopband

Li, Rui; Kim, Dong-Il; Choi, Chang-Mook

Journal of Navigation and Port Research 2006;30(7):607-610.
Published online September 30, 2006.

Compact Low-Pass Filter with Sharp Skirt Characteristics and Broad Stopband

Abstract

A new compact microstrip low-pass filter and its equivalent-circuit model are developed. The philosophy if the structure behind this novel microstrip low-pass filter is simple as it is composed of a pair of symmetrical parallel coupled-line and an open-stub. With this configuration, a finite attenuation pole near the stopband cutoff frequency is available and adjustable by simply tuning the circuit parameters. Furthermore, the rejection bandwidth if this type if low-pass filter am be extended In order to validate the feasibility of the proposed design method, a low-pass filter based on a microstrip structure is designed, fabricated, and measured Experimental results agree very well with the simulation and analytical results.

Key Words: Finite attenuation pole;Low-pass filter;Microstrip structure;Symmetrical parallel coupled-line