Title :
A new compact low-pass filter with broad stopband and sharp skirt characteristics
Author :
Li, Rui ; Il Kim, Dong
Author_Institution :
Dept. of Radio Sci. & Eng., Korea Maritime Univ., Busan, South Korea
Abstract :
In this paper, we proposed a new compact microstrip low-pass filter with broad stopband and sharp skirt characteristics. The philosophy of the structure behind this novel microstrip low-pass filter is simple as it is composed of a pair of parallel coupled-line and an open-stub. With this configuration, a finite attenuation pole near the stopband cutoff frequency is available, and the notch frequency can be well controlled by adjusting the circuit parameters. The design formulas are derived by using an equivalent-circuit model of a parallel coupled transmission line. In order to validate the feasibility of the proposed design method, a 3-order Chebyshev low-pass filter with 0.01-dB ripple is designed, fabricated, and measured. Experimental results agree well with the simulation and analytical results.
Keywords :
Chebyshev filters; band-stop filters; equivalent circuits; low-pass filters; microstrip filters; poles and zeros; Chebyshev low-pass filter; broad stopband characteristic; equivalent-circuit model; finite attenuation pole; microstrip low-pass filter; notch frequency; parallel coupled transmission line; sharp skirt characteristic; stopband cutoff frequency; Analytical models; Attenuation; Chebyshev approximation; Coupling circuits; Cutoff frequency; Design methodology; Distributed parameter circuits; Low pass filters; Microstrip filters; Transmission line measurements;
Conference_Titel :
Microwave Conference Proceedings, 2005. APMC 2005. Asia-Pacific Conference Proceedings
Print_ISBN :
0-7803-9433-X
DOI :
10.1109/APMC.2005.1606557