Phase and amplitude anomalies in uniform microstrip arrays

Abstract

The design process of a corporate-fed microstrip patch antenna array relies on the aperture theory, and microstrip circuits design equations. Such an approach usually neglects mutual coupling between array elements, which is known to degrade the array performance. The design of the individual antenna elements can be a straight forward process for canonical shapes on single layer substrates. On the other hand, the design of the feed network is much more sensitive. Line losses and radiation from the feed network can affect the overall performance of the array both in the co-polar and cross-polar radiation patterns [1]. It was also shown that symmetry in the feed network should be maintained to avoid excessive cross-polarization radiation [2].