| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve reception performance of a radio clock, while attaining size reduction and cost reduction thereof, by simplifying the changeover of the gain characteristics of an antenna of the radio clock. <P>SOLUTION: The radio clock 1 is equipped with the antenna 11 to which communication signals including time information are inputted, the ground GND, a metal case 18, a gain characteristics changing part 12 which changes the gain characteristics of the antenna 11, by making the continuity of the ground GND and the metal case 18 intermittent; a receiving part 20 which acquires the time information from the communication signal inputted to the antenna 11; and a control part 14 which gives the gain characteristics changing part 12 an instruction at the intermittence of the continuity, when the time information cannot be acquired from the communication signal inputted to the antenna 11 that has a single gain characteristics, and instructs re-reception by the antennas 11 that have the gain characteristics changed. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
