4-55
The BIDIRECTIONAL ARRAY radiates energy equally in two opposing directions.
The UNIDIRECTIONAL ARRAY radiates energy efficiently in a single direction.
The COLLINEAR ARRAY has elements in a straight line. Maximum radiation occurs at right
angles to this line.
The BROADSIDE ARRAY has elements parallel and in the same plane. Maximum radiation
develops in the plane at right angles to the plane of the elements.
The END-FIRE ARRAY has elements parallel to each other and in the same plane. Maximum
radiation occurs along the axis of the array.
MATCHING STUBS are used between elements to maintain current in the proper phase.
The GAIN OF A COLLINEAR ANTENNA is greatest when the elements are spaced from 0.4 to
0.5 wavelength apart or when the number of elements is increased.
The OPTIMUM GAIN OF A BROADSIDE ARRAY is obtained when the elements are spaced
0.65 wavelength apart.
