Stacked lowpass filter using LTCC technology

In this paper, the design and fabrication of stacked lowpass filter in a low temperature co-fired ceramic (LTCC) technology is presented. The equivalent circuit of lowpass filter is evaluated by microwave network analysis. It is shown in this paper that the filter schematic is built on a coupled line and multi-layer electric coupled structure. The proposed LPF passes GSM band and rejects USPCS, IMT2000, WiBro, Bluetooth/WLAN, satellite DMB. The dimensions of fabricated LTCC lowpass filter are 3.5 mm x 4 mm x 0.33 mm. The proposed filter has been implemented in a five-layer ceramic substrate.