摘要 |
A method and preferred apparatus for introducing radio frequency isolation near the base of a conductive tower to prevent significant flow of RF current into the ground, thereby to produce an elevated vertical antenna. The invention further relates to a method and apparatus for introducing RF power into the upper portion of the isolated tower to cause said portion to radiate or receive at desired frequencies. Isolation and "excitation" are accomplished by the placement of tuned shortened quarter wave conductive sections along selected portions of the tower, the quarter wave sections used for antenna excitation being also used for impedance transformation to match a coaxial transmission line of nominal inmpedance.
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