Embodiments of the present disclosure provide a MIMO communication method and system, and a receiver node. The method includes: receiving, by a number of optical detection modules of a receiver node, optical signals transmitted by a number of optical transmission modules of a transmitter node. Different optical detection modules of the receiver node have different orientations, and different optical transmission modules of the transmitter node have different orientations.

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.

The present invention relates to a fiber branch structure for spatial optical communication for transmitting information by emitting communication light. The fiber branch structure is provided with: a light emitter configured to emit communication light; a light emission controller configured to control the light emitter; an optical fiber configured to transmit the light emitted from the light emitter; a distributor configured to distribute the light, the distributer being optically coupled to an output terminal of the optical fiber; and an optical fiber group optically coupled to a plurality of output terminals of the distributor. According to the present invention, a communication area can be established without blind spots. That is, the fiber branch structure for spatial optical communication according to the present invention includes an optical fiber group optically coupled to a plurality of output terminals of the distributor. A communication area can be established more assuredly by such an optical fiber group, which prevents the optical communication from being interrupted.

In order to improve free space optical communications, an optical communication terminal includes a laser source, a photo detecting apparatus and an optical input/output assembly. These components are controlled by a control logic. In order to have the optical communication terminal to be self-compatible, the optical input/output assembly selectively routes the outgoing beam and incoming beam depending on their respective beam polarization. To this end, the optical input/output assembly may include a polarizing beam splitter together with a quarter-wave plate.

This underwater optical wireless communication system (100) is provided with a plurality of moving bodies (1) capable of moving underwater. The plurality of moving bodies each includes a plurality of optical wireless communication units (2) each configured to perform bidirectional communication between the plurality of moving bodies using communication light beams (30) having wavelengths different from each other in a plurality of directions which are mutually opposite directions. The plurality of optical wireless communication units is configured to perform bidirectional communication between the plurality of moving bodies using communication light beams, the communication beams having the same wavelength with respect to each of the plurality of directions.

In some embodiments, an optical communication system may include an optical source, a modulator, and a photoreceiver. The optical source may be configured to generate a beam comprising a series of light pulses each having a duration of less than 100 picoseconds. The photoreceiver may have a detection window duration of less than 1 nanosecond. When a first pulse travels through a variably refractive medium, photons in the first pulse may be refracted to travel along different ray paths to arrive at the photoreceiver according to a temporal distribution curve. A full width at half maximum (FWHM) value of the temporal distribution curve may be at least three times as large as a coherence time value of the first pulse, and the detection window of the photoreceiver may be at least six times as large as the FWHM value of the temporal distribution curve.

Systems and methods for performing operations based on LIDAR communications are described. An example device may include one or more processors and a memory coupled to the one or more processors. The memory includes instructions that, when executed by the one or more processors, cause the device to receive data associated with a modulated optical signal emitted by a transmitter of a first LIDAR device and received by a receiver of a second LIDAR device coupled to a vehicle and the device, generate a rendering of an environment of the vehicle based on information from one or more LIDAR devices coupled to the vehicle, and update the rendering based on the received data. Updating the rendering includes updating an object rendering of an object in the environment of the vehicle. The instructions further cause the device to provide the updated rendering for display on a display coupled to the vehicle.

Optical ground terminals (OGT) allowing high optical rate communications for line of sight and non-line of sight operating conditions are disclosed. The described devices include a multifaceted structure where optical telescopes, phase array antennas, and arrays of optical detectors are disposed. Methods to calculate angle-of-arrival based the contributions from optical detectors are also disclosed.

A method for establishing a free-space data transmission channel between movable and/or spatially fixed network nodes. Dynamic position information is collected regarding movable network nodes and static position information relating to spatially fixed network nodes. Specific and node-dependent parameters for the fixed network nodes is collected, based on collected dynamic and static position information. A prioritization list is created of the fixed network nodes. Checking occurs, for the network node having the highest priority of the multiplicity of movable or spatially fixed network nodes in the created prioritization list, which of a selection of movable or spatially fixed network nodes are possible for setting up a directional free-space data transmission channel with the network node having the highest priority of the fixed network nodes. A directional free-space data transmission channel is set up.

An object is to provide a communication system, a base station, and a communication method that can avoid a state in which an RF wireless communication cannot be started due to the quality of optical wireless communication.

In an optical communication system according to the present invention, a base station device repeatedly transmits an authentication information frame addressed to a terminal device at a predetermined cycle by the optical wireless communication, the frame including authentication information for connection to the terminal device by the RF wireless communication. Even if the terminal fails to acquire the authentication information at a certain timing due to the quality of optical wireless communication, the communication system has a mechanism that acquires the same authentication information at regular time intervals, so that terminal authentication processing can be performed at the time when the terminal acquires the authentication information.