Ultra wideband tightly coupled reflectarray antenna

Koldaş, Mutlu
In this thesis, an ultra wideband tightly coupled dipole reflectarray antenna is de signed, fabricated, and measured. This reflectarray consists of a wideband log-periodic dipole array feed antenna and a reflecting surface. The unit element of the reflecting surface is a tightly coupled overlapping bowtie dipole attached with a delay line to approach ultra wideband aim. Infinite array approach and Floquet port excitation ap plied in unit cell simulations to obtain reflection phase curves versus the length of the delay line of the dipole. The reflected beam can be adjusted to radiate in a particu lar direction by arranging the delay line lengths of the tightly coupled dipoles at the design step. A MATLAB code is developed with GUI to construct a full reflecting surface after deciding the delay line lengths with respect to input parameters. The code automatically constructs a reflecting surface in CST Studio Suite where the full wave simulations are executed. Then, a 5×20 reflectarray with the beam directed 30 degrees from the broadside is designed and fabricated. Design is validated by the measurements that the fabricated reflectarray is capable to operate from 4 GHz to 10 GHz.


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Citation Formats
M. Koldaş, “Ultra wideband tightly coupled reflectarray antenna,” M.S. - Master of Science, Middle East Technical University, 2022.