Surface-wave effect in a wideband aperture-coupled stacked microstrip antenna array

A wide band aperture coupled stacked microstrip antenna at the Ku band is described. The stacked element design achieves bandwidths in excess of 20%, but when incorporated into an array the gain bandwidth is reduced owing to surface wave excitation. Studying the nature of the surface wave interference can help reduce its impact, thereby retaining almost the full bandwidth of the single element