A high-Q W band tunable bandpass filter

We present a tunable high-Q two pole waveguide bandpass filter at 110 GHz. The demonstrated filter has record performing insertion loss (2 dB) and tuning range (11 GHz) in the W band (75–110 GHz). A sub-micron resolution piezo electric stepper motor is used to actuate a thin film which forms the ceiling of the resonant cavities. This sub-micron actuation effectively tunes the center frequency of the filter. This tunable filter has a variety of uses such as a front-end bandpass filter for multi-band communications, as a filter for rejecting intermodulation products on tunable systems or as a channel select filter.