A tunable Ka-band planar groove gap waveguide resonant cavity

Planar groove gap waveguide (PGGWG) has similar characteristics to substrate integrated waveguide (SIW) in planar media, but with the advantage of DC isolated conducting planes. This work shows how this DC isolation can be exploited for device biasing by presenting an electrically tunable PGGWG resonant cavity. It is shown that varactor tuning is possible without bridging wires or concentric etched rings. A tuning range of 1.4% in a Ka-band cavity is achieved.