| 摘要 |
An antenna with a parallel-ring structure is provided to obtain the same resonance as a helical antenna and to reduce an entire length of the antenna by using change of return loss due to change of a ring thickness or an interval between rings or a diameter of a parallel-ring or length change of a loading portion. An antenna(200) includes a loading portion(201) constructed by a parallel-ring structure. The parallel-ring has rings and a central conductor. Return loss is changed by first thickness, first diameters of the rings, intervals between the rings, and a second conductor of the central conductor. The antenna further includes a monopole antenna and the central conductor is connected to an end of the monopole antenna. The loading portion is connected to an end of the monopole. The monopole antenna is a retractable antenna to be inserted into a mobile communication terminal or be drawn from the mobile communication terminal. |
