Patent ID: 7515920

Claim:
A communication terminal unit comprising: a controlling means for implementing a cell search, while scanning a predetermined search frequency range, the controlling means comprising: a measuring means for measuring a received-signal level by implementing asynchronous detection over the predetermined search frequency range to determined if a desired signal exists in the predetermined search frequency range; and implementing asynchronous detection in steps of a predetermined frequency step width over the predetermined search frequency range and generating a frequency range that has a center frequency at which the received-signal level is higher than a threshold value and generating a synchronous-detection frequency range that has the predetermined frequency step width; and detecting a cell by implementing synchronous detection in steps of the predetermined frequency step width over the synchronous-detection frequency range, wherein the synchronous-detection frequency range over which synchronous detection is to be implemented is adjacent to a synchronous-detection frequency range whose frequency is higher than that of the synchronous-detection frequency range over which synchronous detection is to be implemented, the controlling means starts synchronous detection from the upper-limit frequency of the synchronous-detection frequency range over which synchronous detection is to be implemented.