Aspects are generally directed to free-space transmitters, free-space receivers, and free-space communication methods. In one example, a free-space communication method includes acts of mapping a data payload to one or more symbols based on a symbol set defined by a digital modulation scheme, varying one or more properties of a signal waveform to phase modulate the signal waveform with the data payload, the one or more symbols each having a symbol duration that defines a timing structure of the modulated signal waveform, and fragmenting the timing structure of the modulated signal waveform to conceal one or more waveform properties of the modulated signal waveform.

The present disclosure relates to a triple-hop multiuser relay network. Further, the relay network is comprised of mixed communication mediums (radiofrequency/free-space optical/radiofrequency), and utilizes a generalized order user scheduling scheme for determining the next source or destination to be selected for transmission. Closed-form expressions were achieved to describe outage probability, average symbol error probability, and channel capacity assuming Rayleigh and Gamma-Gamma fading models for the radiofrequency and free-space optical links, respectively. The effects of pointing errors on the free-space optical link were also considered. Additionally, a power allocation algorithm was proposed to optimize power allocation at each hop.

A method for operating a non-track-bound convoy, the convoy having at least one vehicle traveling ahead and at least one vehicle that is contactlessly coupled to the vehicle traveling ahead and directly following the vehicle traveling ahead, in at least a largely automated manner, including: providing that the at least one vehicle directly following the vehicle traveling ahead follows the vehicle traveling ahead by at least largely automatic open-loop/closed-loop control; and effecting a car-to-car communication between the vehicle traveling ahead and the at least one vehicle directly following the vehicle traveling ahead for the automatic open-loop/closed-loop control; in which a photo-optical, an optical-waveguide-less or an optical-fiber-less car-to-car communication is effected in each case between a light wave emitter and a light wave receiver for at least part of the car-to-car communication. Also described is a related driver assistance system and non-track bound convoy.

An ultrafast omnidirectional wireless data transfer apparatus and system. The ultrafast omnidirectional wireless data transfer apparatus includes an array of laser diodes, an array of fast detectors, and a connector for connecting to a sensor, a computer, and/or a network. The array of laser diodes, and the array of fast detectors are housed in a multifaceted geometry in order to provide communication coverage in all directions. In one aspect, each laser in the array of laser diodes operates at different wavelengths. In another aspect, the ultrafast omnidirectional wireless data transfer apparatus includes field programmable gate arrays. In yet another aspect, the ultrafast omnidirectional wireless data transfer apparatus includes an array of collimators that are connected to an optical combiner. In yet another alternate aspect, an ultrafast omnidirectional wireless data transfer system includes several ultrafast omnidirectional wireless data transfer apparatuses which are optically coupled together and communicate in different wavelengths.

Improvements in secure communication using drones. The communication uses aircraft to provide a secure communication link that prevents undesirable reception. The secure link can be between two people, groups or more specific people. Optical transmission can be from laser, infrared, ultraviolet, white light or a particular wavelength of light. One or multiple aircraft to relay information between senders and receivers. The aircraft can be drones that operate within buildings or with overhead aircraft. The aircraft can intelligently follow or lead a person to maintain a line of sight. Each user can have their own tracking aircraft and the aircraft can communicate with each other using light and/or wireless communication to optimize line-of-sight between the aircraft over geographic medium. The geographic medium may include one or more terrain, air, water, and space. The object may be a soldier, vehicle, drone, or ballistic.

Because of the line-of-sight character of optical wireless communication and a limited field-of-view of optical receivers, the coverage of an access point and the overlapping coverage area of adjacent access points in an optical system are smaller as compared to a RF system. It turns more challenging to support an end point (110) to roam securely in an optical multi-cell wireless communication network. To speed up the derivation of a new pairwise transient key with a new access point during a handover procedure, the end point of this invention comprises a controller (118) that is configured to act as a second supplicant (1181), on behalf of a first supplicant (1186) comprised in a host processor (1185), to communicate with an authenticator to establish a new pairwise transient key for the end point (110) and a candidate access point, and an active pairwise transient key with the currently associated access point is used to secure the communication for new key derivation.

In a LiFi network with multiple coordinators, interference in the overlapping areas between the local parts of the network can occur if each coordinator determines its own local time schedule for communicating with devices. To solve this problem, the invention proposes cooperation between the coordinators to determine non-interfering local time schedules whereby the coordinators rely on interference reports from the devices in the overlapping areas and apply a small number of simple rules. The proposed method is simple, scalable and independent from a central unit.

Disclosed are a many-to-many laser communication networking device and a method. The device includes: an optical field array control module, a transceiver lens array module, an array phase detection module, an array characteristic splitting module, a beam switching array module and a signal transmission module. The optical field array control module is configured to receive a plurality of beams of laser light with different angles, and adjust the corresponding angle of the laser. The transceiver lens array module is configured to convert the angle-adjusted laser into beams of second optical fiber light. The array characteristic splitting module is configured to analyze the second optical fiber light to obtain the second characteristic information. The beam switching array module is configured to control the second optical fiber light to be demodulated into baseband signals via a first path or to be forwarded via a second path according to the second characteristic information.

An invisible light communication system can communicate using infrared or ultraviolet light signals to provide more secure communications. The system includes a software definable and hardware configurable transmitter that uses an input, an encoder, an invisible light source, and an optic to transmit an invisible light signal. The system also includes a software definable and hardware configurable receiver that receives the invisible light signal using an optic, a detector, a detector, and an output. Applications for the invisible light communication system include fixed, deployable, vehicle, and wearable configurations for voice, video and data transmission and receipt in support of a variety of use cases: remote sensing; data exfiltration; remote control, ordnance detonation; tactical chat/messaging; point-to-point and point-to-multipoint audio communications; and full motion video.

An apparatus includes a photonic integrated circuit having an optical phased array, where the optical phased array includes multiple unit cells. Each unit cell includes (i) an antenna element configured to transmit or receive optical signals and (ii) a phase modulator configured to modify phases of the optical signals being transmitted or received by the antenna element. The apparatus also includes a gyroscopic sensor configured to sense movement of the photonic integrated circuit, where at least a portion of the gyroscopic sensor is integrated within the photonic integrated circuit.