| 摘要 |
PURPOSE:To prevent the effect on the antenna due to a human body or the like in contact with a case and to attain one antenna to be resonated to two different frequencies. CONSTITUTION:A metallic cylinder 2 whose center axis is continuous to that of an antenna element 1 is provided to a lower end of the rod shaped antenna element 1, a linear metal 3 nearly along with the center axis of the metallic cylinder 2 is connected to the lower end of the antenna element 1 and the linear metal 3 is connected to a feeder 4 under the metallic cylinder 2. Furthermore, a spiral antenna element 6 whose one end connects to the antenna element 1 or the linear metal 3 via a capacitor 5 is provided in the vicinity of the upper part of the metallic cylinder 2. As a result, a mechanical strength is provided with a simple structure and a power loss is reduced. |
