Title :
Harmonic suppression technique based on mode coupling control in microstrip multistage coupled ring bandpass filters
Author :
Griol, A. ; Mira, D. ; Marti, J. ; Corral, J.L.
Author_Institution :
Nanophotonics Technol. Center, Univ. Politecnica de Valencia, Spain
Abstract :
A technique to suppress higher harmonics in coupled ring bandpass filters is proposed and experimentally demonstrated. This technique basically consists of mitigating the coupling mode between the excitation lines and the microstrip ring, which generates the second harmonic ring resonance. This mode suppression is achieved by optimizing the length of an open-end microstrip line connected to the excitation-coupled lines of the filter. A harmonic suppression ratio for the second harmonic greater than 25 dB in a flat bandpass filter centered at 2.5 GHz is experimentally demonstrated.
Keywords :
band-pass filters; coupled mode analysis; harmonics suppression; microstrip circuits; microstrip filters; microwave filters; 2.5 GHz; FDTD methods; coupled ring bandpass filters; excitation lines; excitation-coupled lines; harmonic ring resonance; harmonic suppression; microstrip bandpass filters; microstrip ring; mode coupling control; mode suppression; multistage bandpass filter; open-end microstrip line; second harmonic; Band pass filters; Frequency; Harmonics suppression; Low pass filters; Magnetic resonance; Microstrip filters; Microstrip resonators; Microwave filters; Power harmonic filters; Resonator filters;
Conference_Titel :
Microwave Symposium Digest, 2004 IEEE MTT-S International
Print_ISBN :
0-7803-8331-1
DOI :
10.1109/MWSYM.2004.1338892
