Patent ID: 7126447

Claim:
An RF-MEMS switch comprising: a substrate; a movable element; an RF signal-conducting unit arranged on the substrate; a plurality of movable electrodes disposed on the movable element, having a space provided therebetween in a direction of signal conduction of the RF signal-conducting unit and arranged above the RF signal-conducting unit; a movable electrode displacing unit for displacing the plurality of movable electrodes at the same time in the same direction towards or away from the RF signal-conducting unit; an upper member disposed above the movable element; and at least one fixed electrode disposed on the upper member; wherein when all of the plurality of movable electrodes are displaced in the direction away from the RF signal-conducting unit by the movable electrode displacing unit so as to be disposed at positions where a signal is switched on, conduction of an RF signal of the RF signal-conducting unit is switched on; when all the plurality of movable electrodes are displaced in the direction towards the RF signal-conducting unit by the movable electrode displacing unit so as to be disposed at positions where the signal is switched off, conduction of the RF signal of the RF signal-conducting unit is switched off; and an electrical length of the RF signal-conducting unit sandwiched between the plurality of movable electrodes is set such that an amplitude of a combined signal composed of RF signals reflected at positions of the RF signal-conducting unit facing the plurality of movable electrodes is less than an amplitude of each of signals reflected at positions of the RF signal-conducting unit facing the plurality of movable electrodes when the plurality of movable electrodes are disposed at positions where the signal is switched on.