LTCC-based optically tunable microwave filter

Advanced microwave wireless devices are needed to dynamically adapt to field conditions. One possible approach for circuit tunability is optical control. In this paper a new optically tunable filter concept is proposed based on LTCC technology and new photoconductive polymer materials. The theoretical foundations of a tunable resonator, simulations of resulting filter performance, specifications of required material properties and basic measurements of this new tunable filter are presented. Finally, a proposed design for an LTCC-based optically controlled filter is given. The feasibility of a filter whose center frequency switches from 8.8 GHz to 6.2 GHz with polymer material having either σ <; 10-3 S/m or σ > 10+5 S/ m, is shown.