Investigation on Different Forms of Circular Sectored-Dielectric Resonator Antenna for Improvement in Circular Polarization Performance

In this communication, some investigations have been performed on different forms of circular sectored-dielectric resonator antenna (CS-DRA) formed using different sector angles (β) to improve the circularly polarized (CP) performance. The additional parameters of CS-DRA are aspect ratio (α) and sector angle (β), which constitute a new optimization framework to analyze CP parameters. These compact structures (CS-DRAs) with simple coaxial probe feeding offer low-volume geometry with wide axial-ratio (AR) bandwidth as compared to conventional DRAs. Based on the results obtained in this investigation, it is found that appropriate values of “α” and “β” could be chosen to improve the CP performance in terms of wide AR, and thus could not be avoided. In this communication, the fundamental mode TMv,1,δand next lower resonant mode TM2v,1,δhave been excited to achieve the orthogonal polarizations. CS-DRA with the best performance has been fabricated to validate the simulation results. Simulated and measured AR bandwidths obtained are 15.2% (5.47-6.37 GHz) and 15.46% (5.43-6.34 GHz), respectively, whereas input reflection coefficient bandwidths are 58.5% (4.24-7.75 GHz) and 48.3% (4.65-7.6 GHz), respectively.