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In this letter, we propose and experimentally demonstrate a space‐fed beamforming approach capable of steering beams up to ±70° with a focal ratio (F/D) reduced to 0.27 and a scan loss remained 4 dB. It is implemented based on an mmWave phase reconfigurable metasurface, and an unconventional array‐fed architecture. By doing so, while the total profile of conventional space‐fed phased arrays can be significantly reduced, specifications such as scan range and scan loss can be simultaneously improved. Compared with conventional phased array systems, such specifications are unique, and can be used to realize low‐profile, cost‐effective, space‐fed phased arrays requiring ultrawide coverages at mmWave frequencies. [ABSTRACT FROM AUTHOR]

The existence of a non-electrically-small scatterer adjacent to the source can severely distort the radiation and lead to a poor electromagnetic compatibility. In this work, we use a conducting hollow cylinder to shield a cylindrical scatterer. The cylinder is shelled with a single dielectric layer enclosed by an electromagnetic metasurface. The relationship between the scattering field and the surface impedance is derived analytically. By optimizing the Fourier expansion coefficients of the surface impedance distribution along ϕ-dimension, the scattering cross-section can be effectively reduced. This unidirectional cloaking method is valid for both TM/TE and non-TM/TE incident field and is not limited to a plane-wave incident field. The accuracy and effectiveness of the method are verified by four cloaking scenarios in microwave regime. We demonstrate that with the surface impedance obtained by the proposed method, a metasurface is designed with physical subwavelength structures. We also show a cloaking scenario under a magnetic dipole radiation, which is closer to the case of a realistic antenna. This method can be further applied to cloaking tasks in terahertz and optical regimes.