| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a helical antenna which improves receiving sensitivity.SOLUTION: In a helical antenna 10, a rod 12 is inserted inside of a coil ring of a spirally wound antenna wire 11. The rod 12 is inserted inside of the coil ring of the antenna wire 11 in such a manner that a portion of an outer peripheral surface of the rod 12 is brought into line-contact with the antenna wire 11 and the remaining portion of the outer peripheral surface is not brought into contact with the antenna wire 11. A square bar of which the cross section is polygonal is used for the rod 12, and the rod 12 is inserted into the coil ring of the antenna wire 11 in such a manner that the antenna wire 11 is brought into point-contact with a part of vertices in the polygonal sectional shape of the rod 12 and is not brought into contact with any side in the polygonal sectional shape of the rod 12.</p> |
