Increasing the directivity of a microstrip patch array by genetic optimization

Abstract

Conventional single element microstrip patch
antennae have a . In order to increase
the directivity, an array of microstrip patches can be used. It
may be possible to further improve the performance of arrays
by applying genetic algorithms (GA). This paper presents a
method to increase the directivity of a 2 × 1 patch array with
broadside radiation using GA. The proposed GA method divides
the patch area into different cells, taking into account that cells
have a small overlap area between them. The patch array is
etched on a substrate with a relative permittivity of 3.38 and a
thickness of 1.52 mm. The antenna operates at 4 GHz resulting
in a directivity of 10.9 dB. The specialty of this design is the
use of GA to select the inter-element spacing, optimized shape
and the feeding position instead of a known shape and a fixed
inset length of feeding. The results show that the directivity of
the genetic array is larger than that of the conventional array
with the same overall dimensions, which resonates at the same
frequency.