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Updated: May 11, 2025

Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
A method to design polarization reconfigurable antenna with simple switching mechanism and compact size
Thai Nguyen-Dinh1, Tan Dao-Duc2, Dinh Nguyen-Quoc3
1Faculty of Radio Electronics Engineering, Le Quy Don Technical University, Hanoi, 11917, Vietnam.
Abstract:
A reconfigurable antenna with simple polarization switching mechanism and compact size characteristics is presented in this paper. The primary radiating aperture of the proposed design is four parasitic elements arranged in a 2 × 2 configuration. This radiating aperture is coupled with an excitation source whose polarizations can be controlled by a switchable feeding network. By employing only two PIN diodes, the proposed antenna can produce unidirectional beams with different polarizations, including linearly polarized (LP), left-hand and right-hand circularly polarized (LHCP, RHCP) modes. It is worth mentioning that employing a switchable feeding network helps to minimize the negative effect of the biasing circuit to the antenna operation characteristics. Experimental results indicate that the consistent operational bandwidth across all states spans from 2.44 to 2.47 GHz. Furthermore, the recorded broadside gain reaches approximately 4.8 dBi. In comparison with existing studies, the proposed antenna achieves multiple polarization configurations while utilizing the least number of diodes and maintaining a compact design.
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