An underwater communications system may include a first device and a second device being movable relative to one another. The first device may include a first laser transmitter configured to generate a first laser beam having a selectable spatiotemporal beam shape from among a plurality thereof, and a first controller coupled to the first laser transmitter and configured to select a spatiotemporal beam shape for the first laser beam from among the spatiotemporal beam shapes. The second device may include a second laser receiver configured to receive the first laser beam, and a second controller coupled to the second laser receiver.

An interference canceling subsystem for a bidirectional communications network includes an input interface configured to receive a first data signal from a first transceiver of the network, an output portion configured to receive a second data signal from a second transceiver of the network, a first signal path connecting the input interface to the output portion, a second signal path connecting the output portion to the input interface, and a first interference canceler disposed between the output portion and the input interface along the second signal path. The first signal path is configured to relay the first data signal from the input interface to the output portion. The interference canceler is configured to (i) relay the second data signal from the output portion to the input interface, and (ii) remove portions of the first data signal from the relayed second data signal prior to reaching the input interface.

A transceiver comprises a transmitter including a light source, a modulator coupled to the light source, a driver that drives the modulator according to a set of driving conditions to cause the modulator to output optical signals based on light from the light source, and an output that passes first portions of the optical signals output by the modulator. The transceiver further comprises a first detector that detects second portions of the optical signals output from the modulator, and a receiver including a second detector that detects optical signals from an external transmitter.

A radio communication system for duplex communication comprising an optical carrier generator for generating optical carrier signals, a local oscillator (LO) for generating an electrical signal in a radio communication band, an information signal source, electro-optic modulators driven directly at an input electrical port by said information signal and said LO signal to modulate a portion of said optical carrier signal to form a modulated portion being an optical band information signal for transmission over an optical link; and a photodetector remote from said electro-optic modulators for receiving said transmitted optical band information signal from said optical link, and directly generating an electrical signal that is up-converted for radio transmission, or down-converted to a baseband frequency.

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.

A communication device includes an interleaving unit that determines an interleaving length of transmit data to be transmitted through free-space optical communication, and interleaves the transmit data based on the determined interleaving length, and a shaping unit that shapes the interleaved transmit data so as to make the interleaving length detectable on a receiving side of the free-space optical communication.

A spatial optical transmitter modulates an optical signal of a single wavelength in accordance with a signal to be transmitted, divides the modulated optical signal into two, rotates polarizations of the two divided optical signals, and transmits the two optical signals as optical signals of two orthogonal polarizations to space.

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.

An optical communication system that includes terminals that operate with different, widely separated wavelengths in which a terminal in the system may be configured to function in both a first operational mode and in a second operational mode. For example, a terminal according to the techniques of this disclosure may communicate with full duplex communication by transmitting a first optical wavelength and receiving a second optical wavelength while in the first operational mode. The same terminal may be reconfigured to transmit the second optical wavelength and receive the first optical wavelength while in the second operational mode. In some examples, the terminal may be located in a spacecraft, such as an orbiting satellite or other vehicle, and may communicate with other terminals such as airborne terminals, terminals located at ground station on the Earth's surface, or with terminals located in other spacecraft.

A vehicle is provided that includes a battery management system with an energy storage device configured to power the vehicle. The energy storage device includes a battery module with: at least one sensor, a processor, and an optical transceiver. The battery management system also includes a control unit to control the energy storage device, and a control unit optical transceiver configured for bidirectional free-space optical communication with the battery module optical transceiver via a free-space optical communication link. The battery module processor is configured to receive sensor readings and transmit them to the control unit via the free-space optical communication link. Based on the sensor readings, the control unit sends commands to the battery module processor via the free-space optical communication link.