Microstrip antennas on very small ground planes for portable communication systems

A limited number of investigations have been reported in the literature about microstrip antennas on small size ground planes. That is because a complete theoretical analysis of an arbitrary shaped microstrip antenna on a substrate of finite dimensions is a difficult task, and no single approach can be conveniently used for the accurate prediction of the radiation patterns. However, most of the investigated sizes of the truncated ground planes are still relatively large. In this paper, the effect of the size of the ground plane on the radiation patterns of the microstrip antenna was studied experimentally, where very small sizes of ground planes were considered. In this study, only rectangular microstrip antennas were investigated because most portable equipment boxes are rectangular in shape.>