| 摘要 |
Transmission antenna formed of several antenna elements and provided with a switching device making it possible to change the conditions of use of the antenna elements and hence the antenna's firing axis. The antenna is formed of n (n: integer greater than 2) antenna elements P1-P5 regularly distributed over a circle C, at the centre O of which is placed a cubicle M which receives the antenna's supply line AO and which includes the switching device as well as tuning circuits. The device makes it possible to go from a first antenna structure in which the antenna elements have, distributed as active elements, reflectors and possibly directors, to a second structure in which the roles of the antenna elements are the same as in the first structure to within a rotation by a given integer number of times 360 DEG /n; thus the firing axis also incurs this rotation and the antenna can fire along n distinct axes with n similar patterns respectively. Application, in particular, in hectometre waves. <IMAGE>
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