| 摘要 |
PURPOSE: To attain ease of matching in the contained state of the antenna similarly to the case of the antenna in the prolonged state by adjusting a length from an antenna connection part to an end of a coaxial line to adjust the impedance toward the coaxial line when viewed from the antenna connection part in the contained state of the rod antenna up to an infinite impedance. CONSTITUTION: When an antenna 4 for a portable telephone set is contained in its main body 1, a part from an antenna connection point 4c to a short- circuiting block 4j is connected like a coaxial line. Since the distance is at leastλ/2, the impedance when viewing the block 4j from the connecting point 4c is adjusted to be an infinite impedance by moving the block 4j. Thus, the impedance when viewing a shield tube 4e from the connecting point 4c is an infinite impedance when the antenna 4 is contained similarly to the case that the antenna 4 is prolonged telescopically and the connecting point 4c is matched. Thus, the matching is obtained easily by the antenna connecting point 4c.
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