A millimeter-wave frequency synthesizer generates a millimeter wave by photomixing two Kerr-soliton microcombs. A single-frequency laser beam is modulated to create first and second pump components having first and second pump frequencies. The first pump component excites a first microresonator to create a first microcomb while the second pump component excites a second microresonator to generate a second microcomb. A pair of comb lines from the two microcombs is detected to generate a low-frequency beat note that is phase-locked by identically tuning the pump frequencies. Another pair of comb lines is detected with a high-speed photodiode to generate the millimeter wave. The frequency of the millimeter wave is based on (i) the difference between the pump frequencies, (ii) the difference between the repetition rates, and (iii) the index of the comb lines that are photomixed to generate the millimeter wave.

A lens antenna array system for wireless communication is provided that includes a transmitter having a first lens and a receiver having a second lens. The transmitter transmits a first plurality of RF signals across a plurality of near-field communication links to the receiver. Based upon a first signal quality determination at the receiver, the transmitter adjusts a plurality of gains to increase a signal quality for a second plurality of RF signals transmitted across the plurality of near-field communication links.

A lens antenna array system for wireless communication is provided that includes a lens antenna array transmitter having a first lens and a lens antenna array receiver having a second lens. The lens antenna array transmitter transmits a plurality of RF signals across a plurality of near-field communication links to the lens antenna array receiver.

Optical switch and modulator devices are described, usable for Terahertz data communication rates. The device comprising an optically transmissive substrate configured for propagating electromagnetic radiation therethrough and a metamaterial arrangement optically coupled to said substrate. The metamaterial arrangement comprises at least one layer of metamaterial particles optically coupled to at least some portion of said optically transmissive substrate, and at least one nanomesh layer made of at least one electrically conducting material placed over at least some portion of the at least one metamaterial layer. The at least one nanomesh layer configured to discharge electrons into the at least one metamaterial layer responsive to electromagnetic or electric signals applied to the metamaterial arrangement, and the at least one metamaterial layer configured to change from an optically opaque state into an optically transparent state upon receiving the discharged electrons, to thereby at least partially alter electromagnetic radiation passing through the substrate.

Optical switch and modulator devices are described, usable for Terahertz data communication rates. The device comprising an optically transmissive substrate configured for propagating electromagnetic radiation therethrough and a metamaterial arrangement optically coupled to said substrate. The metamaterial arrangement comprises at least one layer of metamaterial particles optically coupled to at least some portion of said optically transmissive substrate, and at least one nanomesh layer made of at least one electrically conducting material placed over at least some portion of the at least one metamaterial layer. The at least one nanomesh layer configured to discharge electrons into the at least one metamaterial layer responsive to electromagnetic or electric signals applied to the metamaterial arrangement, and the at least one metamaterial layer configured to change from an optically opaque state into an optically transparent state upon receiving the discharged electrons, to thereby at least partially alter electromagnetic radiation passing through the substrate.

A THz waveguide is described, comprising four conductive wires separated by an air gap, the THz waveguide allowing low-loss and dispersion-free propagation of a THz signal. The system for terahertz polarization-division multiplexing comprises at least two THz sources, a THz waveguide and a THz receiver, wherein said THz waveguide comprises four conductive wires separated by an air gap; THz pulses from the THz sources being coupled into the THz waveguide; the THz waveguide transmitting the THz pulses independently, the THz waveguide operating as a broadband polarization-division multiplexer. The method for terahertz polarization-division multiplexing, comprising multiplexing THz pulses from terahertz sources in free-space, coupling resulting multiplexed THz pulses into a THz waveguide comprising four conductive wires separated by an air gap; and demultiplexing the multiplexed THz pulses after propagation in the waveguide.

A communication network system is a communication network system that distributes information to a plurality of terminals inside a closed space. The communication network system includes a network server and a plurality of lighting fixtures each having an antenna that transmits and receives millimeter-wave-band communication signals to and from the terminals.

A communication system and method is described, including two or more transceivers at different locations, in which a region of the atmosphere at an altitude ranging from 150-350 KM is modified by applying an E-Field strength of 0.2 V/m to create a High-Frequency Ionized Lines/High-Frequency Plasma Lines (HFIL/HFPL) region. The HFIL/HFPL region provides a means for incoming RF transmission signals to be isotropically repeated and received by transceivers at other distant locations within line-of-sight of the HFIL/HFPL region. Incoming RF transmissions into the HFIL/HFPL region may use radio frequencies ranging from 100 MHz-20 GHz. The system described offers a means for users to transmit data from one over-the-horizon location to another at distances up to 4800 km without wires or physical satellites.

A communication system and method is described, including two or more transceivers at different locations, in which a region of the atmosphere at an altitude ranging from 150-350 KM is modified by applying an E-Field strength of 0.2 V/m to create a High-Frequency Ionized Lines/High-Frequency Plasma Lines (HFIL/HFPL) region. The HFIL/HFPL region provides a means for incoming RF transmission signals to be isotropically repeated and received by transceivers at other distant locations within line-of-sight of the HFIL/HFPL region. Incoming RF transmissions into the HFIL/HFPL region may use radio frequencies ranging from 100 MHz-20 GHz. The system described offers a means for users to transmit data from one over-the-horizon location to another at distances up to 4800 km without wires or physical satellites.

Described is a method of setting up a plurality of quantum communications links, forming a quantum network providing provably secure communications and internet services over intercontinental distances without requiring direct line of sight communication or the intermediate use of the entanglement resource of satellites. Also described is a quantum communicator device for use in this method. Two or more quantum memory units are disposed at a first location, an entangled link is set up between at least two of the quantum memory units, at least one of the quantum memory units sharing in the entangled link is physically transported to a second location. The quantum communicator device comprises communications nodes, an optical interface to set up entanglement to other devices and storage nodes, each node in the form of a quantum memory unit capable of storing quantum information for a desired length of time, i.e. weeks or longer.