We develop a transmission line with a floating electrode (FE) arranged on a coplanar waveguide (CPW), and we propose using this transmission line to reduce the decay time of a microwave-band liquid crystal loaded device. Using the proposed CPW-FE structure makes it possible to control both the rise time and decay time by varying the applied bias field, thereby allowing the decay time to be reduced. In the 18GHz band variable phase shifter we developed, we obtained a rise time of 75 Ills and a decay time of 200 ms with a 500 mu m wide CPW center conductor, a gap of 2011111 between the center conductor and ground plane, and a liquid crystal layer thickness of 50 mu m. Under these conditions, the birefringence Delta epsilon' of the liquid crystal was 0.23.