Abstract: An electromagnetic invisibility cloaking device with a broadened cloaking bandwidth and/or a tunable frequency of operation. The cloaking device includes an object (e.g., antenna) and a metasurface (301) that conforms to the surface design of the object. The metasurface includes an array of metal cells (302A, . . . , 302Y), where each of the metal cells includes a circuit element (304) (e.g., active, passive, negative impedance converter element). The array of metal cells may be represented as an array of metal square patches, a mesh grid, horizontal or vertical conductive strips, or any arbitrary combination of unit cell patterns, where each opening, or a subset of them, in such an array includes an embedded circuit element. By incorporating the circuit elements in the conformal metasurface, the cloaking bandwidth is broadened and the frequency of operation is actively controlled and tuned.

Abstract: Modulation patterns for surface scattering antennas provide desired antenna pattern attributes such as reduced side lobes and reduced grating lobes.

Abstract: Surface scattering antennas with lumped elements provide adjustable radiation fields by adjustably coupling scattering elements along a wave-propagating structure. In some approaches, the surface scattering antenna is a multi-layer printed circuit board assembly, and the lumped elements are surface-mount components placed on an upper surface of the printed circuit board assembly. In some approaches, the scattering elements are adjusted by adjusting bias voltages for the lumped elements. In some approaches, the lumped elements include diodes or transistors.

Abstract: Surface scattering antennas on curved manifolds provide adjustable radiation fields by adjustably coupling scattering elements along a wave-propagating structure.

Abstract: Described embodiments include an antenna, method, and an apparatus. The antenna includes a sub-Nyquist holographic aperture configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface with tangential wavenumbers up to the free-space wavenumber (k0). In an embodiment, the antenna is configured to beam radiofrequency electromagnetic power. In an embodiment, the antenna is configured to transfer radiofrequency electromagnetic power.

Abstract: Described embodiments include a system, method, and apparatus. The system includes an antenna comprising a sub-Nyquist holographic aperture configured to define selectable arbitrary complex radiofrequency electromagnetic fields on a surface of the antenna. A mapping engine models an environment within a space radiateable by the antenna. The environment includes a target device and a human being. An optimization circuit selects responsive to the model of the environment a power transmission regime. The power transmission regime includes radiation pattern shaped to wirelessly transfer electromagnetic power from the antenna to the target device without exceeding a radiation exposure limit for humans. A gain definition circuit selects a complex radiofrequency electromagnetic field implementing the selected power transmission regime from the at least two selectable arbitrary complex radiofrequency electromagnetic fields.

Abstract: Described embodiments include an antenna, method, and an apparatus. The antenna includes a sub-Nyquist complex-holographic aperture configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface with tangential wavenumbers up to 2? over the aperture element spacing (k_apt=2?/a).

Abstract: Described embodiments include a system, method, and apparatus. A system includes an antenna comprising a sub-Nyquist holographic aperture configured to define selectable arbitrary complex radiofrequency electromagnetic fields on a surface of the antenna. A path analysis engine tests power transmission pathways from the antenna to a target device located in an environment within a space radiateable by the antenna. The environment includes a human being. An optimization circuit selects responsive to the tested power transmission pathways a power transmission regime. The regime includes an electromagnetic radiation pattern shaped to transfer radiofrequency electromagnetic power from the antenna to the target device without exceeding a radiation exposure limit for humans. A gain definition circuit selects a complex radiofrequency electromagnetic field implementing the selected power transmission regime from the at least two selectable, complex radiofrequency electromagnetic fields.