Improvement of characteristics of microstrip antennas using unbalanced structures

To improve the characteristics of microstrip antennas, an idea of utilizing unbalanced structures in the analysis and design is proposed. In the characterization, the method of moments procedure is employed and the Rao-Wilton-Glisson (1982) basis functions are used in the analysis of microstrip patch antenna. Green's functions in closed form are used, so the analysis is quite fast and efficient and the design result is very useful. The frequency dependent characteristics of a single-patch and two double-patch antennas are analyzed. The design results show that the voltage standing-wave ratio of double-patch antennas can be significantly improved using unbalanced structures.