Premium
Spurious responses suppression of parallel coupled‐lines microstrip bandpass filters: Comparison and improvements of planar approaches
Author(s) -
Roy Marc Le,
Pérennec André
Publication year - 2007
Publication title -
international journal of rf and microwave computer‐aided engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.335
H-Index - 39
eISSN - 1099-047X
pISSN - 1096-4290
DOI - 10.1002/mmce.20204
Subject(s) - spurious relationship , stopband , passband , microstrip , band pass filter , planar , elliptic filter , harmonic , prototype filter , electronic engineering , topology (electrical circuits) , microwave , computer science , physics , filter (signal processing) , control theory (sociology) , acoustics , low pass filter , engineering , telecommunications , electrical engineering , computer graphics (images) , machine learning , computer vision , control (management) , artificial intelligence
In this paper, three methods to reject the first spurious harmonic in parallel‐coupled microstrip filters are investigated. The authors proposed an extension of these approaches to also suppress the second unwanted passbands while keeping the initial passband practically unchanged. Then, two of these techniques are combined to achieve a wider upper stopband. Indeed, the sinusoidal perturbation technique is well combined with overcoupled end sections to reject the first three spurious passbands of an order three filter. A comparison of simulations and experimental results is made, with a discussion on each method efficiency and possible applications to higher order filters. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE 2007.