A prober that has improved positional precision of probing without reducing throughput is disclosed. A movable portion is capable of moving relative to the immovable portion and has a cooling structure defined therein. The condensation unit is disposed in a second fluid passage through which a second fluid flows, and performs heat exchange between the second fluid and the operation fluid. The user equipment, then, transmits a sounding signal through selected number of transmission antennas according to the antenna designation information of the uplink sounding transmission control information element having the shortest cycle period among the plurality of uplink sounding transmission control information elements.