Title :
A compact semi-lumped low-pass filter for harmonics and spurious suppression
Author_Institution :
Comput. & Commun. Res. Labs., Ind. Technol. Res. Inst., Hsinchu, Taiwan
fDate :
3/1/2000 12:00:00 AM
Abstract :
A semi-lumped parallel resonance circuit was employed to design a very compact low-pass filter. The semi-lumped shunt arm consists of a capacitor and a transmission line section. In such an arrangement, two finite attenuation poles can be generated near the passband edge. As a result, the proposed filter enjoys sharper cutoff and fewer filter orders than those of the conventional low-pass filters. In addition, these two attenuation poles can be properly designed to suppress the second and third harmonics generated from power amplifier and frequency source. A low-temperature cofired-ceramic (LTCC) multilayer-ceramic (MLC) low-pass filter and a PCB low-pass filter with a 0402 chip capacitor were designed and tested. Experimental results demonstrate the capability of this filter in harmonics and spurious suppression
Keywords :
UHF filters; harmonics suppression; linear network synthesis; low-pass filters; passive filters; poles and zeros; 0402 chip capacitor; 1.5 GHz; 560 MHz; LTCC MLC low-pass filter; PCB low-pass filter; capacitor; compact low-pass filter; finite attenuation poles; harmonics suppression; low-temperature cofired-ceramic; multilayer-ceramic filter; parallel resonance circuit; second harmonic suppression; semi-lumped low-pass filter; semi-lumped shunt arm; spurious suppression; third harmonic suppression; transmission line section; Attenuation; Capacitors; Distributed parameter circuits; Low pass filters; Passband; Power harmonic filters; Power system harmonics; Power transmission lines; RLC circuits; Resonance;
Journal_Title :
Microwave and Guided Wave Letters, IEEE
