Integrating microstrip filters using LTCC technology for microwave purposes

This paper presents planar microwave and millimeter wave filters in interdigital and combline technique for HIPERLAN applications and integration in LTCC-modules. All filters were simulated on dielectric ceramic with /spl epsiv//sub r/=7.8 and 18. The coupling behaviour of striplines and microstrip lines on this ceramic material was investigated first. The design and simulation of LTCC bandpass filters, the design parameters of which were extracted from an existing ceramic resonator filter design, named hybrid-type, is also reported. The simulated results of both, classic interdigital and hybrid-type, show a satisfying performance in insertion loss, bandwidth and steepness when integrated in LTCC modules.