| 摘要 |
<p>A spiral antenna has a structure in which there may be a small gap (d1) between a feeder spring (117) and a fitting (112) connected with the proximal end (120) of the spiral antenna when a whip antenna (101) is pushed into the case (110) of a cellular phone. The gap provides capacitance of an equivalent impedance characteristic to a monopole antenna (114). The capacitance and the coil of the spiral antenna (113) cooperate to form an LC series resonance circuit that allows the spiral antenna (113) to operate over a wide range of frequencies.</p> |
