Patent ID: 6323745
Filing Date: 2001-11-27
Classification: H01P

Abstract:
A bandpass filter, comprising:a substrate, having a ground plane on one side;a plurality of resonator elements, each having an elongated inductive portion and a capacitive portion, said inductive portions being substantially parallel to each other, wherein each of said inductive portions electrically connects to said ground plane at the end opposite to said capacitive portion, said plurality of resonator elements having a first resonator element, a middle resonator element, and a last resonator element, wherein said middle resonator element is placed opposite to said first and last resonator elements;a first tap electrically connected to a first elongated inductive portion to serve as an input to said filter; anda second tap electrically connected to a last elongated inductive portion to serve as an output to said filter;wherein each of said capacitive portions is comprised of printed elements represented by transmission lines, wherein said transmission line for said capacitive portions of said first and last resonator elements is comprised of a wide width transmission line and said transmission line for said middle resonator is comprised of a ""T"" shaped transmission line with the upper portion of the ""T"" shape comprising said capacitive portion, wherein said middle resonator element is longer in length than said first and last resonator elements by an amount L and wherein said capacitive portions of said first and last elongated inductive portion are bent, so as to be parallel to said first and second taps, and beveled at the inner edges to minimize the transition from inductance to capacitance.