Abstract: An apparatus grouping data units for optical network units into groups of Encapsulation Method, EM, frame(s), wherein a respective group of EM frame(s) include data units addressed to a respective subset of ONUs, generating, based on the groups of EM frame(s), a Framing Sublayer payload including at least one specific frame, wherein, the specific frame includes a length indicator determined in relation to the length of the group(s) of EM frame(s) that is(are) directly following the specific frame and is(are) addressed to at least one subset of ONUs; instructing the ONUs assigned to at least one of said at least one subset to process the EM frame directly following the specific frame, and instructing the ONUs not assigned to the at least one subset to process the EM frame that is indicated by the length indicator of the specific frame; and transmitting the Framing Sublayer payload to the ONUs.

Abstract: Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.

Abstract: A diverged beam optical transmitter is provided that includes a laser source configured to emit a light beam, and one or more lenses. The diverged beam optical transmitter also includes a diffuser placed between the laser source and the one or more lenses, and configured to increase an intrinsic divergence of the light beam and to fill some portion of the one or more lenses such that the light beam is eye safe after the one or more lenses.

Abstract: The present invention enables shortening the time required for resuming communication in a protection method that uses a backup path in an optical communication system that includes a master station device and multiple slave station devices. The slave station devices are connected to a loop path in parallel. The communication paths between the master station device and the slave station devices include a normal path and a backup path. The master station device executes communication control processing with respect to the slave station devices based on the RTTs. A first slave station device is a slave station device that cannot perform communication via the normal path. If the first slave station device is detected, the master station device calculates a first backup path for the first slave station device based on a first RTT between the master station device and the loop path, a loop RTT required for one full lap on the loop path, and the first normal path RTT for the first slave station device.

Abstract: Systems and methods are described for transmitting information optically. For instance, a system may include an optical source configured to generate a beam of light. The system may include at least one modulator configured to encode data on the beam of light to produce an encoded beam of light/encoded plurality of pulses. The system may include a spectrally-equalizing amplifier configured to receive the encoded beam of light/encoded plurality of pulses from the at least one modulator and both amplify and filter the encoded beam of light/encoded plurality of pulses to produce a filtered beam of light/filtered plurality of pulses, thereby spectrally equalizing a gain applied to the encoded beam of light. In some cases, the system may slice the beam of slight, to ensure a detector has impulsive detection. In some cases, the system may include a temperature controller to shift a distribution curve of wavelengths of the optical source.

Abstract: Disclosed are an underwater optical communication aiming method and apparatus. The underwater optical communication aiming apparatus may include an optical communication module configured to transmit and receive laser beams and a plurality of acoustic modules spaced apart from one another at given intervals, disposed around the optical communication module, and configured to find a direction or relative distance of a counterpart light source under water. A direction of the optical communication module may be aimed at a counterpart light source found through the acoustic module in order to communicate with the counterpart light source by using the optical communication module.

Abstract: Systems and methods include causing perturbations across optical spectrum; probing responses across some or all of the optical spectrum after the perturbations; and determining a nonlinear transfer function based on the responses. The nonlinear transfer function can include a representation of any of end-to-end channel powers, Signal-to-Noise Ratio (SNR), Noise-to-Signal Ratio (NSR), Bit Error Rate (BER), Q, and Mean Squared Error (MSE).

Abstract: A communication system that includes a cloud server that obtains first sensor data associated with a defined indoor area and second sensor data associated with each of a plurality of optical nodes in defined indoor area. The plurality of optical nodes includes a master communication device, a plurality of optical routing devices, and one or more service communication devices. The cloud server further obtains location coordinates of each of the plurality of optical nodes. The cloud server then causes the master communication device to form a laser beam-based wireless communication network in the defined indoor area. A free-space optical backhaul is constructed by establishing a point-to-point free-space laser link between each pair of optical nodes of the plurality of optical nodes and a RF supervisory link is established between each pair of optical nodes of the plurality of optical nodes for a network monitoring and control function.

Abstract: Provided is a data-coding apparatus that includes: a data-input line for receiving input data; a data scrambler having light sources coupled to the data-input line and modulated in accordance with the input data, and light sensors that receive light from the light sources; and at least one light-sensing processor coupled to the light sources and configured so as to selectively isolate light signals received from individual ones of the light sources based on at least one control signal input into such data scrambler. The light-sensing processor is dynamically controlled by the control signal(s) so as to rearrange words within the input data according to patterns that change in real time.

Abstract: An optical communication system may include microLEDs for use in communicating data between chips or multi-chip modules. The number of microLEDs may be greater than a number of electrical data lines for carrying data to be communicated. Signals on the electrical data lines may be inverse multiplexed, for example to allow for operation of the microLEDs at a rate slower than operation of electrical circuitry generating signals on the electrical data lines.

Abstract: The present application discloses an integrated self-coherent receiving optical chip based on round-trip delay interferometers, including a first beam splitter, a multi-port circulator array, a first round-trip delay interferometer and a second round-trip delay interferometer integrated on a same substrate, wherein the first beam splitter is connected to the multi-port circulator array, and the multi-port circulator array is connected to the first round-trip delay interferometer and the second round-trip delay interferometer, respectively.

Abstract: 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.

Abstract: Systems and methods for performing signed matrix operations using a linear photonic processor are provided. The linear photonic processor is formed as an array of first amplitude modulators and second amplitude modulators, the first amplitude modulators configured to encode elements of a vector into first optical signals and the second amplitude modulators configured to encode a product between the vector elements and matrix elements into second optical signals. An apparatus may be used to implement a signed value of an output of the linear processor. The linear photonic processor may be configured to perform matrix-vector and/or matrix-matrix operations.

Abstract: Systems, devices, and methods for laser-based communications are disclosed. At least one embodiment relates to laser-mediated underwater communications, in which one or more laser signals transmit encoded information from a transmitter to a receiver. Additionally, an underwater transmitter node sends information to an underwater receiver node using one or more lasers. At least an additional embodiment relates to laser-based communications that may be used to send information across a variety of media (e.g., air, water, etc.). Specifically, a first and a second communications system each sends a laser beam to the other. Each communications system further includes a position sensitive detector (PSD) that obtains positioning and/or steering information of an incoming laser beam and ensures that the positions of both the outgoing laser beam and the incoming laser beam match.

Abstract: An optocoupler circuit includes first and second resistors, an optocoupler, a reference circuit, and a comparator. The optocoupler includes a light source and a phototransistor. The light source is connected to form a first voltage divider with the first resistor. The phototransistor is connected to form a second voltage divider with the second resistor. The optocoupler transitions an output of the second voltage divider between first and second levels. Magnitudes of the first and second levels are greater than zero. The reference circuit is configured to output a reference voltage. The comparator includes a first input and a second input. The first input receives an output of the first voltage divider. The second input receives the reference voltage. An output of the comparator transitions between a third level and a fourth level based on a comparison between the output of the first voltage divider and the reference voltage.

Abstract: A system and method are provided herein for communicating with and controlling various devices using visible light communication (VLC). According to one embodiment, a method is provided for extending a communication range of a VLC system comprising a plurality of controlled devices and a remote-control device. Such a method may include, for example, transmitting a communication message from a remote-control device to a first controlled device located within range of the remote-control device, wherein the communication message is transmitted through free space using visible light, and extending the communication range of the VLC system to a second controlled device, which is located outside of the range of the remote-control device, by using the first controlled device to retransmit the communication message through free space using visible light to the second controlled device.

Abstract: A communication system that includes a cloud server that obtains first sensor data associated with a defined indoor area and second sensor data associated with each of a plurality of optical nodes in defined indoor area. The plurality of optical nodes includes a master communication device, a plurality of optical routing devices, and one or more service communication devices. The cloud server further obtains location coordinates of each of the plurality of optical nodes. The cloud server then causes the master communication device to form a laser beam-based wireless communication network in the defined indoor area. A free-space optical backhaul is constructed by establishing a point-to-point free-space laser link between each pair of optical nodes of the plurality of optical nodes and a RF supervisory link is established between each pair of optical nodes of the plurality of optical nodes for a network monitoring and control function.

Abstract: This application provides an example base station for an example wireless communication network and an example method. One example base station includes a central unit and a remote radio unit (RRU). The RRU includes one or more antennas. The RRU is coupled to the central unit via one or more optical transmission fibers. Each optical transmission fiber defines a respective downlink transmission channel for transmitting a respective downlink transmission signal from the central unit to the respective antenna of the RRU. The RRU is configured to provide a respective uplink feedback signal based on the respective downlink transmission signal via an uplink feedback channel to the central unit.

Abstract: An apparatus includes baseband processing circuitry configured to generate a baseband signal that is transmitted to a first network element and a second network element, and an optical power supply configured to generate a first optical signal and a second optical signal, transmit the first optical signal to the first network element, and transmit the second optical signal to the second network element. The first optical signal and the second optical signal include information that enables synchronization of the first and second network elements.

Abstract: A communication network system is a communication network system that distributes information to a plurality of terminals inside a closed space. The communication network system includes a network server and a plurality of lighting fixtures each having an antenna that transmits and receives millimeter-wave-band communication signals to and from the terminals.