Abstract:

A novel microstrip bandpass filter (BPF) with two transmission zeros is presented. This filter has a wide upper stopband by using two novel slow-wave resonators. With an “N+2” coupling matrix method, the filter is easy to design and has high frequency selectivity. Measured results show that the filter has good response performances including low insertion loss of 1.66 dB at the center frequency 2.4 GHz, and upper stopband frequency up to 7.0 GHz. These are in good agreement with simulation.

Key words: bandpass filter (BPF); slow-wave resonator; coupling matrix; transmission zero