Mm Band Ltcc High-q Filters Are Developed

Two high Q bandpass filters at millimeter wave band based on Substrate Integrated Waveguide(SIW) and Low Temperature Co-fired Ceramics(LTCC) are designed in this thesis, and one is realized. The filter takes the advantages of low cost, small in size, light in weight, etc., and can easily be integrated into microwave and millimeter wave integrated circuitsFirstly, the LTCC technology was introduced and a test circuit based on the resonate method of microstrip ring was designed to test the performance of LTCC for dielectric constant and loss.The SIW was analysed by the poynting's theorem and EDA software. The relation between the leakage of electromagnetism energy and structure size was obtained. A transition of microstrip to waveguide based on SIW technique was processed with LTCC to validate the feasibility of SIW.Then, a SIW resonator was analyzed. The equivalent electrical wall of metallized via arrays was obtained. Therefore analysis of resonator was predigested. Graphs of the external Q and coupling coefficient between resonators were created.With the theory and the graphs, the initial sizes of BPF were obtained, and then the final sizes were obtained by the software simulation.Finally, a chebyshev function BPF with SIW resonator was designed and realized by LTCC with 12-layer substrate. A high performance elliptic function BPF with SIW resonator was designed .