Terahertz reflectarray and transmitarray

摘要

Reflectarrays and transmitarrays are extremely important in the applications of terahertz (THz) technologies, as they feature merits like high gain and low cost. In this work, a reflectarray and a transmitarray are designed at 300GHz. A 32 × 50 offset-fed wideband reflectarray antenna, based on single-layer elements with a large and linear phase response, shows a fixed beam direction without frequency dispersion over a large frequency band of 0.225 ~ 0.325THz and a gain of 30.76 ~ 33.98dBi. The designed three-layer transmitarray element can provide 360° phase coverage with transmission coefficient over -0.9dB. Simulations show that the three-layer transmitarrays, fed by a 15-dBi horn with a focal to diameter ratio (F/D) of 0.88, achieves peak aperture efficiency of 68% with a 1-dB gain bandwidth of 23%. The transmitarrays fed by an open-ended waveguide with F/D = 0.3 are fabricated and measured for verification purpose.