Comb-Shaped Patch Antenna Design Study with Shifted Arms and Asymmetric Architecture Enabling Controlled Resonance Change and Radiation Pattern

Abstract

This paper reports comb-shaped patch antennas with asymmetrical geometries having two and three arms on the sides. The proposed geometry is evolved from regular rectangular shaped patch antenna by removing certain parts of the radiator patch and shifting the arms on one side of the antenna. Systematic simulations were obtained with the designed antennas for different arm shifting distances, and changes in resonance behavior and far-field radiation pattern were investigated. Results show that as the arm shifting increases the first and second resonance frequencies of the antennas decrease. Also, it is observed that the radiation occurs with two symmetric beams at the second resonance frequency of the designed antennas with no shift between the arms. However, as the arm shifting is applied the beam on the side of the arms closer to the feeding line gets stronger, whereas the other beam weakens. Obtained plots indicate that the directivity of the antennas have a tendency to increase with the arm shifting while the side lobe level decreases. In addition, results show that the half power beam width of the antenna increases with arm shifting. The simulations were repeated for different arm thicknesses and the same observations were held.