Monolithic microwave bandpass filters design for S- and C- bands

This paper discusses the development of monolithic integrated circuits of S- and C-band bandpass filters from modeling to measurement of experimental samples within the pHEMT05D technology. Bandpass filters with central frequencies of 2.5, 3 and 5 GHz with a relative bandwidth of 40% and a rejection in the stop band of at least –30 dB have been developed. When developing the topology, optimization methods were used according to the requirements for frequency characteristics. Two variants of carrying out measurements of experimental samples are proposed: with welding on PCB using the Kulicke & Soffa 4256 station and from the plate using the Cascade Microtech EP6RF probe station. The measurements were carried out using the Rohde Schwarz ZVA40 vector network analyzer. The obtained samples showed deviations in frequency characteristics of approximately 10% and an increase in losses in the passband within 2 dB. High repeatability of the result within the manufactured plate is demonstrated, which confirms the stability of the obtained result.