Abstract: There is provided a scattering element comprising a vertically-oriented waveguide comprising one or more dielectric components configured to provide directional scattering of an incident electromagnetic wave in a pattern caused by one of interference between at least two guided components and interference between at least one guided component and at least one radiative component, the guided and radiative components excited by the incident electromagnetic wave. A grating device for transmission or reflection of incident electromagnetic waves in a desired direction, the grating device comprising an array of the scattering elements, is also provided.

Abstract: Orbital angular momentum (OAM) communications systems provide an additional degree of freedom to the electromagnetic waves that travel between the transmission and receiving stations, thereby enabling a dramatic increase in data transmission rates. The present invention provides a design for a very low reflectivity flat spiral phase plate that generates OAM modes and a method of making the same. The design incorporates variable sizes of perforated unit cells and may include matched layers to provide improved impedance matching, and the flat disc shape makes the phase plate compact and easy to install. The OAM phase plate can be designed to operate at frequencies from a few 100s KHz to ultraviolet frequencies and is capable of providing one or more OAM modes at the operational frequencies, irrespective of polarization. In a preferred embodiment, the OAM phase plate is designed for operation at about 30 GHz frequency, with 20 GHz bandwidth.

Abstract: Embodiments herein provide a system for underground communication. The system includes a surface layer and an underground layer. The surface layer includes an unburied transceiver station connected to a base station. The underground layer includes a buried transceiver station connected to the unburied transceiver station. The underground layer includes an electronic device with a meta-material antenna and a transceiver in communication with the buried transceiver station. Further, the underground layer includes a coordinator in communication with a plurality of sensors nodes and a plurality of routers. The underground layer includes an unburied transceiver station in communication with the plurality of routers and meta-material antenna. The unburied transceiver station in underground layer communicates with the buried transceiver station.

Abstract: Embodiments herein provide a system for underground communication. The system includes a surface layer and an underground layer. The surface layer includes an unburied transceiver station connected to a base station. The underground layer includes a buried transceiver station connected to the unburied transceiver station. The underground layer includes an electronic device with a meta-material antenna and a transceiver in communication with the buried transceiver station. Further, the underground layer includes a coordinator in communication with a plurality of sensors nodes and a plurality of routers. The underground layer includes an unburied transceiver station in communication with the plurality of routers and meta-material antenna. The unburied transceiver station in underground layer communicates with the buried transceiver station.

Abstract: Orbital angular momentum (OAM) communications systems provide an additional degree of freedom to the electromagnetic waves that travel between the transmission and receiving stations, thereby enabling a dramatic increase in data transmission rates. The present invention provides a design for a very low reflectivity flat spiral phase plate that generates OAM modes and a method of making the same. The design incorporates variable sizes of perforated unit cells and may include matched layers to provide improved impedance matching, and the flat disc shape makes the phase plate compact and easy to install. The OAM phase plate can be designed to operate at frequencies from a few 100s KHz to ultraviolet frequencies and is capable of providing one or more OAM modes at the operational frequencies, irrespective of polarization. In a preferred embodiment, the OAM phase plate is designed for operation at about 30 GHz frequency, with 20 GHz bandwidth.