Modified Equivalent Circuit Model of Microwave Filter with LTCC Technique

Because microwave products in the consumer electronics market are continuous developing, device and component manufacturers have to seek new advanced integration, packaging and interconnection technologies, as size, cost and performance are critical factors for the success of a microwave product. One of the most promising integration technologies is the multilayer low temperature co-fired ceramic technology (LTCC). In this technology, passive components, such as inductors, capacitors and filters, are integrated into multilayer LTCC substrate. The purpose of this paper is to address the special method that should be considered for designing LTCC microwave filter. It is given how to get equivalent circuit about multilayer ceramic microwave filter that is striplines configuration or LC configuration, especially, modified equivalent circuit model is proposed, where the relation between the lumped parameters and physical dimension of LTCC microwave filter is discussed. The capacitance and inductance matrix of LTCC microwave filter is obtained using the fast multipole method. Finally, two microwave filters are designed by the novel design method of field-circuit and HFSS. The novel design method of field-circuit is more efficient, therefore, the designing time can be shortened.