Design of a W -Band GaAs-Based SIW Chip Filter Using Higher Order Mode Resonances

In this letter, an on-chip bandpass filter is designed and implemented based on a 70-μm GaAs substrate integrated waveguide (SIW) technique for W-band integrated transceiver applications. To achieve a high-frequency selectivity, a modal bypass coupling realized by higher order mode resonators is introduced in the SIW filter, and two designable transmission zeros are generated accordingly. The presented filter has a center frequency of 92.7 GHz, with a 3-dB bandwidth of about 3.2 GHz. The measured out-of-band rejection is better than 30 dB at 90 and 95 GHz, respectively.