A Standing-Wave Microstrip Array Antenna

The design and analysis of a single-layer standing-wave microstrip array antenna are presented. No quarter-wave transformers or power dividers are present in the design. The main emphasis of this paper is on the multiple reflections in the feedline causing a standing-wave of a higher-order mode. As in the radiating patches of the array, the feedline resonates as well. So the array is treated as an arbitrarily-shaped microstrip antenna and the generalized cavity model is applied for analysis due to its simplicity and physical insight. The accuracy of the model is verified by simulation and experiment. Spurious radiations and manufacturing difficulties can be minimized in such single-layer standing-wave designs when compared to corporate-fed traveling-wave structures. The scheme offers good potential for building large arrays for high-gain applications.