Wireless communication device and transmission-power control device

The purpose of this wireless communication device is, when transmitting data to another communication device, to identify, from among a plurality of antennas, an antenna that can transmit said data using a lower transmission power. This wireless communication device is characterized in that: said wireless communication device switches between a first antenna and a second antenna each time a request signal is transmitted to another communication device; and the transmission power used to transmit said request signal is increased or decreased each time the wireless communication device switches between the first antenna and the second antenna.