| 摘要 |
<p>An antenna for small mobile devices comprises an antenna rod (1) retractable in an antenna cover (2), the rod having either an extended position, when the device operates in an active mode, or a retracted position, when the device operates in a passive mode. The electrical length of the antenna is different in the respective modes. Further, the antenna rod (1) comprises an upper section (3) and a lower section (4), separated from each other by an intermediate electrically insulating part (7), wherein the upper section (3) forms an antenna in a passive mode and the two sections (3, 4) in the active mode.</p> |
