A High-Efficiency Transmitarray Antenna Using Double Split Ring Slot Elements

This letter present a high-efficiency transmitarray antenna using a four-layer double split ring slot structure as the unit cell element. The transmission coefficient of the element at different incident angles is analyzed by Ansoft HFSS, and the results show that the element has the advantages of low transmission loss and less sensitivity to the incidence angle of the electric field. A high-efficiency transmitarray antenna composed of four layers of double split ring slot elements is designed, manufactured, and tested at Ku-band. The diameter of the transmitarray antenna is 6.76 wavelengths, and the measured gain is 23.9 dB. Radiation efficiency of 77.6% and aperture efficiency of 55% are achieved at a center frequency of 13.58 GHz in this design. The measured 1-dB and 3-dB gain bandwidths are 7.4% and 17.7%, respectively.