| 摘要 |
<P>PROBLEM TO BE SOLVED: To control the timing of cell search executed during standby of a portable telephone and to save electric power while ensuring communication state. <P>SOLUTION: The portable telephone stores a first threshold value for comparing with a reception level and a second threshold value which is equivalent to a reception level lower than the first threshold value and information on base stations for selectively receiving signals from several base stations. It detects the reception levels of the signals received from the several base stations according to the information on the base stations. When the reception level of all the signals from the detected several base stations is equal to or lower than the first threshold value and the reception level of at least one signal is higher than the second threshold value, cell search is executed at a first interval of time. When the reception level of all the signals from the several base stations is equal to or lower than the second threshold value, cell search is executed at a second interval of time shorter than the first interval of time. <P>COPYRIGHT: (C)2007,JPO&INPIT |
