An uplink transmission band and a downlink transmission band that are allocated to each of a plurality of users are determined based on allocation information indicating allocation of a frequency bandwidth available to each of the plurality of users, and are output as uplink transmission band allocation information and downlink transmission band allocation information, respectively. Based on the downlink transmission band allocation information, downlink signals output from a plurality of wireless control devices toward a plurality of wireless devices for each of the plurality of users, and the uplink transmission band allocation information are multiplexed, and the multiplexed signal is demultiplexed into downlink signals for each of the plurality of users and the uplink transmission band allocation information. Based on the demultiplexed uplink transmission band allocation information, the uplink transmission band allocated to each of the plurality of users is changed, and uplink signals output from the plurality of wireless devices toward the plurality of wireless control devices for each of the plurality of users are multiplexed according to the changed uplink transmission band and then, the multiplexed signal is demultiplexed into the uplink signals for each of the plurality of users.

An adaptive receiver comprising a current buffer, an inverter-based transimpedance that receives input from the current buffer, an average current control loop that feeds back from the inverter-based transimpedance to the current buffer, a variable gain circuit that receives input from the inverter-based transimpedance, a differential voltage amplifier that receives input from the variable gain circuit, an automatic gain control loop that feeds back from the differential voltage amplifier to the inverter-based transimpedance and variable gain circuit, and a differential buffer that receives input from the differential voltage amplifier.

A method communicates data with a platform. A platform receives modulated coherent optical signals modulated using radio frequency signals encoding sensor data and generates an input current in response to receiving the modulated coherent optical signals at a receiver system in the platform. The platform recovers the radio frequency signals from the input current in a manner that adjusts for changes in the modulated coherent optical signals caused by variations in received optical intensity occurring during propagation of the modulated coherent optical signals. The platform outputs the radio frequency signals encoding the data.

Disclosed herein are embodiments of an aerial network system including a first transceiver configured to transmit and receive free space optical (FSO) signals and a second transceiver configured to transmit and receive radio frequency (RF) signals. A processor provides modulated data signals to the first and second transceivers for transmission and receives demodulated signals from the first and second transceiver. The processor is configured for policy-based multipath admission of requests for access to an IP-routing enabled overlay network. The processor includes an inverse mission planning system configured for predictive traffic load balancing of transmitted FSO signals and RF signals. The inverse mission planning system includes radio behavior models and aerial platform models, and is configured for geographic simulation and optimization of mission planning data based upon user-inputted mission-specific data. Forward error correction (FEC) coding of transmitted communications via packet erasure coding provides resiliency with a low bit error rate.

A method for transmitting information across a water-air interface with a ultraviolet (UV) beam, the method including emitting the UV beam in a first medium, with a first optical wireless communication device; measuring a scintillation index of the UV beam in a second medium, different from the first medium, at a second optical wireless communication device; selecting, based on a value of the scintillation index, a modulation scheme for the UV beam; and modulating the UV beam with the selected modulation scheme. The UV beam has a wavelength in a range of 100 to 400 nm.

A technology is described for optical communication. An example of the technology can include receiving an event stream containing indications of independent events detected by pixels in an event camera. An event may be a change in brightness detected by a pixel in the pixel array, and the pixel independently generates an indication of the event in response to detecting the event. The event stream can be demultiplexed into a plurality of communication streams containing related events associated with a plurality of communication sources. The events contained in a communication stream can be aggregated based in part on an event proximity and an event time that associates an event with other events contained in the event stream. The plurality of communication streams can be demodulated to extract optically transmitted information from the plurality of communication streams, which can be sent to a data consumer.

Communication systems and methods for high-data-rate, high-efficiency, free-space communications are described. High-speed optical modems and automatic repeat request can be employed to transmit large data files without data errors between remote devices, such as an earth-orbiting satellite and ground station. Data rates over 100 Gb/s can be achieved.

Methods, devices, and systems are described for free space optical communication. An example device can comprise a defocuser configured to receive an optical signal from a laser and control a beam divergence of the optical signal. The device can comprise a controller configured to cause the defocuser to adjust the beam divergence based on an operational mode of the laser.

A light-receiving device includes: a light guide plate of a transparent member having a first surface and a second surface as principal surfaces opposed to each other and an emission surface formed on at least one end of the transparent member; a lens sheet having lenses and is disposed opposite to the first surface; a support member that supports the lens sheet such that a distance between the principal surface of the lens sheet and the second surface is equal to the focal distance of the lenses; a directional light-guide layer that is disposed on the second surface of the light guide plate and guides, toward the emission surface, the travel direction of an optical signal entering the light guide plate; and a receiver that receives the optical signal emitted from the emission surface of the light guide plate and converts the received optical signal into an electric signal.

The purpose of the present invention is to provide an optical/RF wireless hybrid communication system and a control method capable of solving the instability of link conditions of an RF wireless link and an optical wireless link. In the optical/RF wireless hybrid communication system and the control method according to the present invention, links for data transmission are not limited to one of an RF wireless link and an optical wireless link, the quality of link conditions is determined from signal quality received through channels of both the RF wireless link and the optical wireless link, and the distribution of data to be transmitted through the respective links is determined on the basis of the determination result. Thus, the links can be flexibly switched depending on the transmission conditions such as disturbance.