| 摘要 |
PURPOSE:To stabilize the input impedance and to improve the efficiency by leading a conductor in parallel from the feeding conductor and the grounding conductor at the top of a grounded antenna, arranging the conductors in a curved shape in parallel with ground and short-circuiting the tip so as to increase the radiation resistance. CONSTITUTION:The conductors 24, 25 are led from the ground conductor 22 and the feeding conductor 23 in parallel from the top of the grounded antenna 21, the conductors 24, 25 are curved in parallel with ground 26, arranged, for example, concentrically to constitute a parallel coil 27. A coil 28 is connected to the tip of the parallel coil 27. In this antenna, the parallel coil 27 is constituted to move the antinode of an unbalancing current flowing in the same direction through the ground conductor 22 and the feeding conductor 23 upward and to increase the radiation resistance. Further, the parallel coil 27 acts like decreasing the current (balanced current) flowing oppositely through the ground conductor 22 and the feeding conductor 23, resulting that the earth loss is minimized. Thus, the height of the antenna is lowered to improve the radiation efficiency.
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