Abstract
In this paper, a tightly coupled dipole reflectarray antenna as well as a variant-coupling-capacitance method to improve the antenna aperture efficiency is presented. Tightly coupled elements and true-time-delay lines are employed in the design of a wideband reflectarray. The proposed reflectarray can operate from 2 GHz to 5 GHz with the gain varying from 11.3 dBi to 21 dBi. Moreover, we propose a variant-coupling-capacitance method to improve the reflectarray aperture efficiency at lower frequency. By changing the coupling capacitance between neighboring elements according to their positions in the reflecting surface, a more linear equivalent distance delay line is achieved. Hence, phase error is reduced. According to measurement, the reflectarray gain in 2 GHz using the proposed method is increased by 3 dBi compared with the previous design. Aperture efficiency in 2 GHz is improved by 21.6%.
Highlights
Reflectarray (RA) antennas are a new generation of high-gain antennas thanks to their distinguishable electrical and mechanical characteristics
We present a tightly coupled dipole reflectarray antenna (TCDRA)
To state the good property of the proposed antenna, the performance of some recent wideband reflectarray antennas reported in the literature and the variant-coupling-capacitance tightly coupled dipole reflectarray antenna (VTCDRA) in this paper are summarized in table 3
Summary
Reflectarray (RA) antennas are a new generation of high-gain antennas thanks to their distinguishable electrical and mechanical characteristics. We develop a variant-coupling-capacitance method in which we change the value of lp of each element according to its position to attain a more linear equivalent distance delay. Using this method the gain in lower frequency can be improved without deteriorating higher frequency performance. In (8), n is the number of elements between ei and the center element which is in the same row with ei.The updated equivalent distance delay for elements with variant coupling capacitance is shown in Fig. 5 in line with dots. The physical aperture area of the VTCDRA is 120743mm while the physical aperture area of the TCDDRA is 113360mm
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
