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Horizontal Director-Reflector Array

Author: Edmund A. Laport

Additional gain can be obtained with two parasitic elements, one a director and the other a reflector, on opposite sides of the active element.

FIG. 3.34. Geometry of horizontal dipole with parasitic reflector.

The plan and side views and one set of essential electrical dimensions are shown in Fig. 3.36, together with the horizontal pattern.

FIG. 3.36. Director-reflector array. (Data by Brown.)

The vertical pattern for the array over ground at a height h would be derivable from the measured horizontal pattern by the relation


The empirical characteristics of this type of antenna make it necessary to follow closely the principle of similitude in attempting to reproduce a prescribed design. The cross-sectional scale must also be retained faithfully.

This type of antenna can also be used as a single-mast rotary beam for the higher frequencies.

Last Update: 2011-03-19