Implementation of millimetre-wave bandpass filter with MMIC technology

This study presents the implementation of a millimetre-wave bandpass filter with conventional MMIC technology. The filter utilises the inductive π-network coupling structure to minimise the effect of process variation and achieve the desired circuit characteristics. The filter is very compact in size and can be precisely predicted by a commercial EM simulation tool. A 26 GHz filter prototype is designed and fabricated. The measured passband insertion loss is about 5 dB and the attenuations at the stop bands are all greater than 20 dB.