Axial Ratio Enhancement of a Single-Layer Microstrip Reflectarray
Farias, R. L.
; Heckler, M. V. T.
; Schlosser, E. R.
IEEE Antennas and Wireless Propagation Letters Vol. 18, Nº 12, pp. 2622 - 2626, December, 2019.
ISSN (print): 1536-1225
Journal Impact Factor: 1,312 (in 2008)
Digital Object Identifier: 10.1109/LAWP.2019.2945641
This letter presents a new approach for the enhancement of the axial ratio (AR) of a single-layer circularly polarized reflectarray antenna based on a circular microstrip patch with phase delay line stubs unit-cell. The AR improvement is achieved by inserting insets around the two stubs, changing the orientation of one of them and using a mirror symmetry arrangement. Two prototypes have been designed, fabricated and tested to proof the proposed concept in K-band. Good agreement has been obtained between numerical simulations and experimental results. The measured results confirm a remarkable AR improvement with values below 1 dB and 3-dB gain and AR bandwidths larger than 23.7%.