Design of Miniature Bandpass Filters on an Organic Laminate Substrate Using a Modified T Prototype

This paper presents very small bandpass filters embedded in an organic laminate substrate for wireless system-in-package applications. Due to the lack of a fabrication process for high capacitance density capacitors on the applicable substrate, the proposed bandpass filter designs are based on a modified T prototype. By carefully taking parasitic and coupling effects into account in the filter synthesis procedure, the presented bandpass filter designs can feature themselves with a third-order Chebyshev response plus multiple transmission zeros, resulting in a low insertion loss in the passband as well as a high attenuation rate in the roll-off region. Comparison among circuit analysis, EM simulation and measurement shows good agreement.