An experimental study of microstrip antennas on very high permittivity ceramic substrates and very small ground planes

An experiment al study of rectangular microstrip antennas on two ceramic composite substrates, barium-titanate with a dielectric constant of 37 and neodymium-titanate substrates with a dielectric constant of 85, is presented. The measured results for radiation patterns, cross-pol levels and resonant frequencies for antennas with ground planes as small as 1 " X 1 " are given. It is shown that, for very small ground planes, the far-field pattern is smooth and nearly omnidirectional in both E and ii planes, a feature that may be of interest in many mobile applications.