C and Ka-Band Wide Bandpass Filter Using LTCC Technology

This paper presents two types of wideband filters that have been developed at 5 and 28-GHz frequency bands, respectively. These filters have been fabricated with low temperature co-fired ceramics (LTCC) multilayer technologies. Each filter has approximately 20% and 12% 3dB bandwidth, insertion loss less than 1.5 dB, and has an attenuation over 30 dB at fit plusmn15% respectively. Design procedure is described and design examples are given to demonstrate the features of the proposed coupling structure. A wide-band LTCC filter is simulated and successfully built. The advantages of multilayer LTCC technology such as high integration and vertical stacking capabilities were employed to design edge- coupled embedded microstrip wide BPF. The difficulties in controlling the precise distance between two adjacent resonators in LTCC edge-coupled BPF were overcome by locating the resonators on different layers.