Title :
Design of CT and CQ filters using approximation and optimization
Author :
Levy, Ralph ; Petre, Peter
Author_Institution :
R. Levy Associates, La Jolla, CA, USA
fDate :
12/1/2001 12:00:00 AM
Abstract :
A new design technique for cascaded triplet (CT) filters has been derived commencing from the well-known Chebyshev all-pole prototype filter. One or more finite frequency poles may be introduced by cross coupling across sets of three nodes, and the filter rematched by a reasonably accurate approximate compensation of the element values. Any general optimizer may then be used to obtain a nearly perfect result without undue concern over convergence failures. A previous similar theory for cascaded quadruplet sections is generalized and may be combined with the CT theory to form filters having both types of sections. The theory is applied to both singly and doubly terminated filters and may include poles on the real axis of the s-plane for delay equalization
Keywords :
Chebyshev filters; band-pass filters; cascade networks; circuit optimisation; equivalent circuits; low-pass filters; lumped parameter networks; microwave filters; poles and zeros; Chebyshev all-pole prototype filter; approximate compensation; bandpass filter; cascaded quadruplet filters; cascaded triplet filters; cross coupling; cross-coupled filters; delay equalization; design technique; doubly terminated filters; equivalent circuits; filter optimization; filter synthesis; finite frequency poles; general optimizer; low-pass filter; lumped-element circuit; sets of three nodes; singly terminated filters; Attenuation; Chebyshev approximation; Convergence; Delay; Design optimization; Filtering theory; Frequency; Laboratories; Low pass filters; Prototypes;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
