A wideband and low‐profile transmitarray antenna using different types of unit‐cells.

A wideband low‐profile transmitarray antenna has been designed. Several prototypes of unit‐cells with different transmission phase shift ranges are used to constitute the antenna. To achieve wideband performance, the transmission phase versus frequency curves of these unit‐cell prototypes are required to be nearly parallel in the working frequency band. Also, two or more unit‐cell prototypes instead of a uniform prototype are used to avoid introducing air gaps and reduce the thickness of transmitarray, which is commonly used in transmitarray design. A wideband millimeter wave dual‐polarized transmitarray with a thickness of only 0.12λ0 is designed, fabricated, and measured. It is demonstrated that the antenna has a wide 1‐dB gain bandwidth of 20.2% (31‐38 GHz), a gain higher than 31.4 dBi, and a peak aperture efficiency of 41.3%. Good agreement between simulations and measurement is achieved. [ABSTRACT FROM AUTHOR]