A guided-wave-driven metasurface antenna includes an input for receiving a guided wave; an output for outputting a free-space wave; and a spatial frequency mixer connected between the input and the output for converting the guided wave to the free-space wave. The spatial frequency mixer is implemented by a metasurface of the antenna. The superheterodyne metasurface can be fabricated with high accuracy using lithography step similar to conventional waveguides made by the well-established semiconductor processing technology, making their integration with PICs straightforward.

A system to detect obstacles includes a power beam transmission circuit, a power beam reception circuit arranged to receive a power beam from the power beam transmission circuit, an emitter module, and a detector module arranged to distinguish between a first characteristic and a second characteristic. The emitter module includes a first emitter arranged to emit a first signal having the first characteristic, the first signal emitted in proximity to the power beam, and a second emitter arranged to emit a second signal having the second characteristic, the second characteristic different from the first characteristic, the second signal emitted in proximity to the first signal. The detector module includes a first detector arranged to respond to the first signal emitted by the first emitter, wherein the detector module is arranged to determine when an obstacle is in or near a line-of-sight transmission path between the first emitter and the first detector.

A method (100) for managing Optical Wireless Communication (OWC) in a User Equipment (UE) is disclosed, the UE being configured for Radio Frequency (RF) communication with a network and comprising at least two OWC receivers. The method comprises monitoring a captured luminous flux intensity at the OWC receivers (1 10) and, if a captured luminous flux intensity at at least one of the OWC receivers is above a viability threshold (120), selecting the OWC receiver having the highest captured luminous flux intensity (130) and extracting client data from an optical signal received on the selected OWC receiver (140). Also disclosed are a UE (300, 700) configured for RF communication with a network and for OWC, the UE comprising at least two OWC receivers, and a controller (500, 600) for managing OWC in a UE.

A modulating circuit adapted to modulate between an energy harvesting mode and a wireless transmitter mode is disclosed which includes a solar cell, an energy-harvesting circuit, a first switch coupling the solar cell to the energy harvesting circuit and controlled by a first control line, a second switch coupling the solar cell to a programmable current source and controlled by a second control line, a transmitter/energy harvesting mode circuit adapted to select between a transmitter mode and an energy harvesting mode, and a symbol-to-current mapping circuit adapted to encode data to be communicated by the solar cell, the symbol-to-current mapping circuit adapted to adjust the programmable current source to thereby provide a metered current to the solar cell.

A method for a system includes broadcasting with a first transceiver of a transit terminal to a smart device, a first identifier, receiving with the first transceiver from the smart device, an ephemeral ID not permanently associated with a user of the smart device, providing with the first transceiver to the smart device, a second identifier and a unique data packet, receiving with the first transceiver from the smart device a token determined by an authentication server in response to the second identifier and the unique data packet and wherein the token comprises a payload portion, determining with a processor of the transit terminal whether the token is valid, and directing with the processor a peripheral device to perform a user-perceptible action for the user, authorizing the user to enter or exit a transit system associated with the transit terminal in response to determining the token to be valid.

Provided are, among other things, systems, methods and techniques for providing remote location-based customer service for in-store customers. One such system includes: (a) a central server; (b) wireless transceivers coupled to the central server at different locations within each of multiple different retail shopping sites; and (c) handheld wireless devices, carried by customers at such retail shopping sites and in wireless communication with such wireless transceivers. Each of the handheld wireless devices is configured with a user interface that allows a customer to designate a user-interface element to request a customer-service session. Upon designation of the user-interface element on one of such handheld wireless devices, the request is forwarded to the central server. The central server establishes a two-way real-time communication link between the handheld wireless device and a customer-service representative.

A mobile system (1,11) comprises a camera (3) and at least one processor (5). The at least one processor is configured to capture an image with the camera, e.g. of a light beacon (15), to determine whether a certain object is recognized in the captured image, e.g. by querying a database (19), and to start detecting and/or decoding data being communicated via visible light in dependence on the certain object being recognized.

A light-receiving device includes: a light guide plate that is a transparent member having, as main surfaces, a first surface and a second surface facing each other and has an emission end formed on at least one end portion of the light guide plate; a wave plate that is disposed on the first surface of the light guide plate and converts an optical signal of circularly polarized light into linearly polarized light; a hologram layer that is disposed on the second surface of the light guide plate and guides a traveling direction of the optical signal converted into the linearly polarized light toward the emission end of the light guide plate; and a light receiver that receives the optical signal emitted from the emission end of the light guide plate and converts the received optical signal into an electrical signal.

A wireless communication system comprises a base station and one or more relay docks and transmits directional wave signals between components using high frequency waves, such as millimeter waves. A beam forming decision engine utilizes position information collected from one or more position or motion sensors of a user device to determine a direction in which to form a directional wave signal being transmitted between components of the wireless communication system.

A switch device is provided. The switch device includes a switch and a one-way link circuit, wherein the switch including a first port, a second port, and a third port. The third port coupled to the second port via a first path and coupled to the first port via a second path. An input terminal of the one-way link circuit is coupled to the first port.