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 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.

Various embodiments are disclosed herein with generally relate to an optical communication system using a photonic lantern. In at least one embodiment, the optical system comprises: an optical transmitter coupled to a signal transmitting path; an optical receiver coupled to a signal receiving path; a photonic lantern, the photonic lantern extending between a first open end and a second open end, the first end comprising an opening to a single multi-mode fiber, and the second end comprising a plurality of single mode fibers that are adiabatically coupled to the multi-mode fiber, the plurality of single-mode fibers includes a single-mode fiber adapted to carry a fundamental optical mode and the remaining single-mode fibers adapted to carry higher-order optical modes, wherein, the single-mode fiber is coupled to the optical transmitting path, the remaining single-mode fibers are coupled to the optical receiving path.

An asymmetric bidirectional optical wireless communication system based on orbital angular momentum comprises a system end device and a client end device. The system can split light into P-polarization beam and S-polarization beam, and utilize the orbital angular momentum multiplexing technology to increase the system capacity for uplink transmission in the client end device. In addition, the system also uses the combination of a beam homogenizer and a spatial light modulator to design an orbital angular momentum multiplexer with low energy loss, which can increase the number of orbital angular momentum channels by increasing the effective area of the components.

A system and method for providing terrestrial and planetary point-to-point, high-altitude platform, and satellite broadband data services by using free-space optical communications link in conjunction with a high-data-rate wideband frequency modulation waveform. The architecture supports data capacities greater than an order of magnitude over the most capable current terrestrial, satellite constellation, and outer space communication systems. The optical links use optical wideband frequency modulation permitting compact optical terminals and avoidance of cost- and mass-intensive digital processing in the communication chain. For terrestrial applications, provided are high-altitude relay platforms to maximize availability and distance between communication stations. For space applications, provided are space-fed lens satellite radio frequency antennas to generate many user beams while employing a novel frequency conversion scheme for compact accommodation on small satellites, overlapping ground coverage from multiple satellites, high-altitude platforms relaying signals between satellites and gateways as needed, and compatibility with conventional radio frequency user terminals.

A free-space optical communication system includes an optical phased array (OPA) photonic integrated chip, a transceiver photonic integrated chip, and one or more processors. The OPA chip includes a plurality of array elements and a plurality of phase shifters. The transceiver chip includes one or more transmitter components and one or more receiver components. The one or more processors are configured to transmit a first signal via the OPA chip and the transceiver chip, and receive a second signal via the OPA chip and the transceiver chip.

The optical tracking module includes an optical phased array (OPA), an analog drive, an integrated photodetector, and one or more processors. The OPA includes a plurality of array elements, and a plurality of phase shifters. The analog drive is configured to adjust the plurality of phase shifters. The integrated photodetector is configured to receive light from the OPA. The one or more processors is configured to extract signal information of an incoming beam via the OPA, and control an outgoing beam using the analog drive based on the signal information. The OPA, the analog drive, the integrated photodetector and the one or more processors are in an integrated circuit.

An optical communication system includes an optical transmitter and one or more processors. The optical transmitter is configured to output an optical signal, and includes an average-power-limited optical amplifier, such as an erbium-doped fiber amplifier (EDFA). The one or more processors are configured to receive optical signal data related to a received power for a communication link from a remote communication system and determine that the optical signal data is likely to fall below a minimum received power within a time interval. In response to the determination, the one or more processors are configured to determine a duty cycle of the optical transmitter based on a minimum on-cycle length and a predicted EDFA output power and operate the optical transmitter using the determined duty cycle to transmit an on-cycle power that is no less than the minimum required receiver power for error-free operation of the communication link.

Embodiments relate to a free space optical (FSO) terminal that transmits and receives optical beams. The FSO terminal includes a fore optic and a rotatable dispersive optical component. A receive (Rx) optical beam from the remote FSO communication terminal is received through the fore optic, and a transmit (Tx) optical beam is transmitted through the fore optic. The dispersive optical component is positioned along the optical paths of both the Rx and Tx optical beams. Since the Rx and Tx optical beams have different wavelengths and the dispersive optical component has a wavelength dependence, the dispersive optical component creates an angular separation between the Rx and Tx optical beams. The controller controls the rotational position of the dispersive optical component (and possibly also the wavelength of the Tx optical beam) to achieve a desired angular separation between the Rx and Tx optical beams.

An assembly for optical to electrical power conversion including a photodiode assembly having a substrate layer and an internal side, an antireflective layer, a heterojunction buffer layer adjacent the internal side; an active area positioned adjacent the heterojunction buffer layer, a plurality of n+ electrode regions and p+ electrode regions positioned adjacent the active area, and back-contacts configured to align with the n+ and p+ electrode regions. The active area converts photons from incoming light into liberated electron hole pairs. The heterojunction buffer layer prevents electrons and holes of the liberated electron hole pairs from moving toward the substrate layer. The plurality of electrode regions are configured in an alternating pattern with gaps between each n+ and p+ electrode region. The electrode regions receive and generate electrical current from migration of the electrons and the holes, provide electrical pathways for the electrical current, and provide thermal pathways to dissipate heat.