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__ForceTOC__ == Introduction == A typical monopole antenna, pictured to the right, has an omni-directional pattern and is limited in its frequency range. Please keep in mind that an omni-directional (see omnidirectional antenna) radiation pattern applies to the azimuth patterns and does exhibit a null at zenith. A monopole antenna can be thought of as a dipole antenna where one end of the dipole antenna now becomes the ground plane for said monopole antenna. By this line of conceptual thinking, one can easily reach the conclusion that the radiation emanating from a monopole antenna exists in half the space of similar dipole antenna. Therefore, the maximum gain is twice that, or an addition 3dB, of the maximum gain of typical dipole. Hence the nominal value of maximum for a monopole antenna is about 5.15dBi. Stutzman puts is succinctly as follows: :''... A monopole is a dipole that has been divided in half at its center feed point and fed against a ground plane...''〔Stutzman, Warren L., and Gary A. Theiele. ''Antenna Theory and Design''. 2nd Ed. New York: 1998. ISBN 0-471-02590-9〕 This article covers one type of dual band blade monopoles. This is the slot inside a monopole. Computational Electromagnetic Modeling (CEM) will be used to give some graphics of operations for a more conceptual understanding. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dual-band blade antenna」の詳細全文を読む スポンサード リンク
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