To fast judge a radio frequency to be operated by a base station in the case of an approach to a communication area in a radio communication to be performed between the base station and a mobile station.
In a radio communication device 1 for the mobile station comprising a radio communication system for transmitting data and communication control information from the base station to the mobile station by using any one of a plurality of radio frequencies, this device is provided with a receiving level detecting means (111) for detecting the receiving levels of signals in a plurality of radio frequency bands, a down transmission presence/absence detecting means 12 for detecting the presence of a base station transmitting signal when the receiving level is equal to or higher than a prescribed receiving level, and a receiving means 11 for receiving the signal. Any one radio frequency is selected in the radio frequency signal bands, and, when the receiving level detecting means is on standby in a state capable of receiving any arbitrary radio frequency signal and the down transmission presence/ absence detecting means 12 detects the base station transmitting signal, the radio frequency of the base station transmitting signal is detected by switching the radio frequency signal to be selected to the other radio frequency in the receiving means 11.
SAKAMOTO TOSHIYUKI
NAGASHIMA TOSHIO
TAKAHASHI JUNICHI
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