Dual-Frequency Reflectarray Based on Split-Ring Slots

Autor: Jose I. Martinez-Lopez, Jovanni Silva-Montero, Alexander E. Martynyuk, Jorge Rodriguez-Cuevas, Jesus A. Ortiz-Fuentes
Rok vydání: 2017
Předmět:
Zdroj: IEEE Antennas and Wireless Propagation Letters. 16:952-955
ISSN: 1548-5757
1536-1225
DOI: 10.1109/lawp.2016.2615049
Popis: This letter presents a dual-frequency reflectarray (RA). This RA is capable of forming two differently oriented main lobes with the same sense of circular polarization in the directions determined by the reflection elevation angles $\theta _{01}$ and $\theta _{02}$ at two closely spaced frequencies. The RA element contains a pair of concentric split-ring slots with different angular rotations. The geometry of the element was modified and optimized to suppress a mutual coupling between the concentric rings. To validate the operation principle, 317-element offset RAs $\text{RA}\_0\_20$ , $\text{RA}\_20\_0$ , $\text{RA}\_30\_40$ , and $\text{RA}\_40\_30$ were designed to operate at 34.5 and 38.5 GHz for the pairs of elevation angles ( $\theta _{01}$ , $\theta _{02}$ ) equal to (0 $^\circ$ , 20 $^\circ$ ), (20 $^\circ$ , 0 $^\circ$ ), (30 $^\circ$ , 40 $^\circ$ ), and (40 $^\circ$ , 30 $^\circ$ ), respectively. Then, these RAs were fabricated and tested. The highest measured aperture efficiency of 0.45 was observed for $\text{RA}\_0\_20$ and $\text{RA}\_20\_0$ at 34.2 GHz, whereas the $\text{RA}\_30\_40$ demonstrated the lowest aperture efficiency of 0.25 at 38.2 GHz.
Databáze: OpenAIRE