A directional free-space optical communication system includes a source device including a laser diode and an endpoint device including a photodiode. The endpoint device and the source device also include an adjustable optics subsystem that increases both angular and positional offset tolerance between the source device and the endpoint device.

Techniques and examples pertaining to single channel line-of-sight (LOS) communication are described. The transmitting end of the LOS communication involves direct modulation of a light emitted from a light emitter. The receiving end of the LOS communication involves receiving a video stream of the light emitter emitting the light, wherein the video stream comprises a plurality of video frames that are continuous in time. The receiving end of the LOS communication also involves converting the video stream to a binary string comprising a plurality of binary bits. Each of the binary bits corresponds to a respective one of the plurality of video frames, and the binary string contains a repeated binary pattern representing a message being conveyed. The receiving end of the LOS communication also involves extracting the binary pattern from the binary string and then decoding the binary pattern to obtain the message.

A method supported by a first terminal is provided herein. To implement the method, a camera of a first terminal performs two or more captures of two or more frames along a line of sight toward a second terminal. A controller of the first terminal manipulates the two or more frames to produce two or more interim images and analyzes the two or more interim images to track a beacon of the second terminal. The controller outputs coordinates with respect to the tracked beacon to a mirror package of the first terminal.

Described are retroreflective marker devices, which encode information that can be read by optical sensors, such as LiDAR devices, and that do not detract from human safety. Also described are kits for retrofitting existing markers.

The present disclosure provides systems and methods for enabling Personal Augmented Reality (PAR). PAR can include an emitor configured to receive data signals and emit the data signals as light signals. PAR can further include a smart device configured to receive the light signals emitted by the emitor. The smart device can process the light signals to yield a communication and display the communication on a screen.

The disclosure provides for a system that includes a plurality of stations equipped for free-space optical communications (FSOC) in a network and a central control system. At least one station in the plurality of stations includes a wavelength selectable switch, an OEO module, and one or more first processors. The one or more first processors are configured to control the wavelength selectable switch, process an electrical signal that is extracted using the OEO module, and communicate with the central control system. The central control system includes one or more second processors that are configured to receive data regarding FSOC communication conditions at the plurality of stations, determine a path between stations through the network based on the received data, and transmit instructions to the plurality of stations.

A free space optical communication system includes an optical receiver configured to receive a light beam from an optical transmitter wirelessly in free space. The optical receiver includes an array of photodetectors and an electrical circuit. The array of photodetectors is configured to receive the light beam and convert optical signals of the light beam into electrical current. The electrical circuit is electrically coupled to the array of photodetectors and is configured to combine electrical current from the photodetectors and output a voltage or current signal.

A dual-mode imaging receiver (DMIR) can acquire and maintain SOA free-space optical communication (FSOC) links without a precision mechanical gimbal. Unlike other FSOC technologies, a DMIR can operate without precise spatial alignment and calibration of the transmitter's or receiver's spatial encoders (precision pointing) in static (fixed point to point) geometries. Instead, a DMIR uses electronic receive beam selection to acquire and track transmitters with coarse mechanical pointing and a single aperture. And because the DMIR can operate with just one aperture, it does not need a beacon at the transmitter since it does not transition from a wide field-of-view acquisition aperture to a narrow field-of-view detection and decoding aperture even in dynamic geometries.

A free-space optical communication method is provided. An example method may include generating an optical frequency comb comprising a first tone and a second tone different from the first tone. The method may include modulating, by a first modulator of a first device, the first tone to generate a first signal comprising data. The method may include modulating, by a second modulator of the first device, the second tone to generate a second signal that is a phase conjugate of the first signal. The method may include transmitting, via free-space and to a second device, a communication signal having the first signal and the second signal.

A free-space optical (FSO) communication system includes a transmitter including a modulated light source and transmit optics for emitting a modulated optical signal into a FS channel toward a receiver. A receiver is coupled to receive the modulated optical signal including receive optics coupled to a few-mode (FM) pre-amplifier that is coupled to a demodulator.