Broadbanding Microstrip Antennas using Unequal Patches

In this paper, a broadbanding concept using unequal patch sizes and without an air region separation is proposed and applied to double and triple patch antennas. In order to show the development of the concept, initially, the single and the double patch microstrip antenna developed on low-profile substrates with the same overall thickness and dielectric constant, are studied. Then the development of the low-profile triple patch antenna on three substrates with the same overall thickness as those of the single and double patch microstrip antenna is reported. The physical appearance of the triple patch antenna is presented. It is fed by a microstrip line connected to the middle patch