A new miniaturized LTCC transversal bandpass filter for RF and microwave applications

Abstract

Actual trend in microwave electronics lies in miniaturization of electronic components with remaining or even improving of its characteristics. A new conception of filter design considering this requirement is presented in the paper. Size reduction is provided using of both LTCC (low temperature cofired ceramic) multilayer technology and system solutions. The filter design is based on transversal and recursive principles which provide easy and flexible design procedure. Characteristics of the filter are not worse then ones of standard resonator filters. The filter can be considered both as a transversal filter and as lumped-element equivalent circuit of a ring resonator with perturbations. Such configuration of the filter provides combination of low insertion loss in passband with high rejection characteristics. As an example, 5 GHz LTCC filter for wireless front-end systems was produced and successfully tested.