Theory and Experiment for Infinite Microstrip Arrays,
ILLINOIS UNIV AT URBANA DEPT OF ELECTRICAL ENGINEERING
Pagination or Media Count:
Because of their unique characteristics, microstrip antennas are particularly well suited for use in large scanning arrays. To obtain greater bandwidth, it is useful to use thicker-substrates, which can increase the effects of mutual coupling and lead to significant mismatch or blindness for certain scan angles. Using an infinite array formulation, the impedance of a single element in an infinite array environment has been solved with the method of moments. Mutual coupling is built into the solution, and the presence of surface waves is accounted for by using the periodic Greens function for the grounded dielectric substrate. An important feature of the solution is an acceleration technique which improves the efficiency by more than an order of magnitude as compared to the standard formulation. Examples are presented demonstrating blindness in arrays of microstrip dipoles on various substrates, both with and without radomes. In addition, examples of the impedance of patch arrays are given. In order to check the validity of the theoretical results, several array configurations, both with and without radome layers, were tested in a simple waveguide simulator, with good results.