| 摘要 |
<p>A directional radar antenna consists of two copper wires (21,21') arranged parallel to one another and wound in regular spirals with one wire rotated 180 deg. relative to the other. A line intersecting the beginning (22, 22') and ends (23, 23') of the wire spirals defines an axis (X) with the spiral beginning equidistant from the spirals' centre (O). Those portions of the wires on one side of the axis (X) have a rate of expansion different to those on the other side by virtue of each spiral being preferably formed from interconnected semi-circular wire portions of successively increasing radius. Alternatively each spiral is a succession of rectilinear members. The distance between the spiral beginnings (22,22') and the central (O) set the minimum value and between the spiral ends (23,23') and the centre (O) the maximum value of the frequency range. High frequency power is applied at the same amplitude by 180 deg. out of phase to the beginnings (22,22'). The antenna enables the direction of a distant object to be determined without reference to the wavelength.</p> |
