Abstract: An optical antenna apparatus for free-space optical communication, includes an input end having a lens positioned to receive one or more incoming optical signals, where the one or more incoming optical signals are received from one or more optical fibers connected at the input end. The optical antenna apparatus further includes an output end having a prism positioned at a defined distance from the lens. The one or more incoming optical signals of the one or more optical fibers passes through the lens and then the prism to form one or more free-space optical beams for a bi-directional free-space optical communication with a remote optical node.

Abstract: A relay device (39bA) includes an optical signal return unit (50a) and a detection unit (55b). When an optical signal input via one optical transmission line (41) of two optical transmission lines (41 and 42) with a double-ring configuration has not been detected for a predetermined time or longer, the detection unit (55b) outputs a disconnection signal of the optical transmission line. The optical signal return unit (50a) is configured to, only when there is an input of the disconnection signal, return to one of the optical transmission lines (41) only a clamp beam that has been sent from a representative node via the other optical transmission line (42) in the direction opposite to the optical signal input via the one of the optical transmission lines (41).

Abstract: A 2×2 optical multi-input-multi-output (MIMO) demultiplexer is disclosed. A first optical phase shifter applies a first relative phase shift between a first pair of optical transmission paths that are received from MIMO inputs, and a first 2×2 optical coupler combines the first pair of optical transmission paths and outputs a second pair of optical transmission paths. A second optical phase shifter applies a second relative phase shift between the second pair of optical transmission paths, and a second 2×2 optical coupler combines the second pair of optical transmission paths and outputs a third pair of optical transmission paths. A third optical phase shifter applies a third relative phase shift between the third pair of optical transmission paths, and a third 2×2 optical coupler combines the third pair of optical transmission paths and outputs a fourth pair of optical transmission paths, which are output by a pair of MIMO outputs.

Abstract: Provided is a high-speed optical transmission-reception apparatus including a digital-signal processing circuit and optical modulation and optical reception modules, in which a flexible printed circuit is used as a high-frequency interface for the optical modulation and optical reception modules, a mechanism for connecting the high-frequency line pattern to the flexible printed circuit is provided on a package substrate of the digital-signal processing circuit, and the package substrate and the optical modulation and optical reception modules are connected by the flexible printed circuit.

Abstract: A 10 G rate OLT terminal transceiver integrated chip based on XGPON and DFB laser includes: a burst mode receiver RX, a continuous mode transmitter TX and a digital control unit DIGIITAL. The burst mode receiver RX amplifies an optical signal from each ONU client into an electrical signal through a burst TIA, processes double-detection for amplitude and frequency of the electrical signal, outputs the signal whose amplitude and waveform pulse width meet the threshold requirements to the host, and uses a fast recovery module to control the timing to meet the XGPON protocol. The continuous mode transmitter TX receives the electrical signal attenuated by the PCB, and selects the bypass BYPASS path or the clock data recovery CDR path according to the degree of attenuation. The digital control unit DIGIITAL is used to provide control signals for the burst mode receiver RX and the continuous mode transmitter TX.

Abstract: An optical antenna apparatus for free-space optical communication, includes an input end having a lens positioned to receive one or more incoming optical signals, where the one or more incoming optical signals are received from one or more optical fibers connected at the input end. The optical antenna apparatus further includes an output end having a prism positioned at a defined distance from the lens. The one or more incoming optical signals of the one or more optical fibers passes through the lens and then the prism to form one or more free-space optical beams for a bi-directional free-space optical communication with a remote optical node.

Abstract: Dynamic radio frequency (RF) beam pattern adaptation in a wireless communications system (WCS) is provided. The WCS typically includes a number of wireless devices, such as remote units and/or base stations, for enabling indoor wireless communications to user devices. The wireless devices are typically mounted on a fixed structure. Notably, a wireless device may be preconfigured to support RF beamforming based on an RF beam pattern that corresponds to a configured orientation. However, the wireless device can be installed with a different orientation from the configured orientation, thus requiring the RF beam pattern to be adapted accordingly. In this regard, a wireless device is configured to dynamically determine an actual orientation of the wireless device and automatically adapt the RF beam pattern based on the determined actual orientation. As a result, it is possible to reduce installation and calibration time associated with deployment of the wireless device in the WCS.

Abstract: According to an aspect of an embodiment, a method may include assigning an activation window by an optical line terminal during a portion of an upstream transmitting window in a passive optical network (PON). The method may include performing a first modification to a first upstream transmission. The method may include performing a second modification to a second upstream transmission. The method may include receiving the first upstream transmission from a first optical network unit (ONU) during the activation window, the first ONU synchronized in the PON. The method may include receiving a second upstream transmission from a second ONU during the activation window, the second ONU requesting activation in the PON.

Abstract: A system, comprising an optical transmitter including a memory and one or more processors, wherein the one or more processors are in communication with the memory and configured to perform creating a first signal and a second signal, wherein the first signal and the second signal are each polarized; rotating a polarization of the first signal and the second signal by ? degrees; adding a differential group delay (DGD) to the second optical signal; generating a first optical signal from the first signal; and generating a second optical signal from the second signal.

Abstract: An upstream resource grant method, a device, a passive optical network, and a computer-readable storage medium are provided. The upstream resource grant method includes: obtaining, by an optical line terminal, an upstream grant message on which transformation processing has been performed, wherein a transformation parameter used for the transformation processing includes a physical identity of an optical network unit (ONU); and sending, by the optical line terminal, the upstream grant message on which the transformation processing has been performed, wherein the upstream grant message carries an upstream resource grant indication of the optical network unit, and the upstream resource grant indication indicates an upstream resource granted to the optical network unit. According to this application, an occurrence probability of a rogue ONU phenomenon is reduced, thereby improving service running stability of a PON system.

Abstract: Dynamic error-quantizer tuning systems and methods prevent misconvergence to local minima by using a dynamic quantizer circuit that controls reference voltages of three or more comparators that are independently adjusted to modify the transfer function of the dynamic quantizer circuit. A weighted sum of the comparator outputs is subtracted from the input to form an error signal in a control loop. The ratio of the reference voltages is chosen to reduce or eliminate local minima during a convergence of the control loop and is set to values that minimize a mean squared error signal with respect to discrete modulation states of the input after the convergence of the control loop is complete.

Abstract: Systems and methods of optimizing launch power for each span in an optical system with a plurality of spans are provided. In an embodiment, a method includes varying power on a span under test of the plurality of spans; observing performance measurements related to of one or more channels, at corresponding optical receivers; and one of setting launch power for the span under test and repeating the varying and observing, responsive to the observed measurements.

Abstract: Optical transmitter includes: signal processing circuit, optical modulator, optical filter, and delay circuit. The signal processing circuit generates N drive signals for generating a modulated optical signal. Symbol rate of the modulated optical signal is fs and each symbol of the modulated optical signal transmits N bits. The optical modulator includes Mach-Zehnder interferometer and N phase-shift segments each of which shifts a phase of light propagating through an optical path of the Mach-Zehnder interferometer according to the N drive signals. The optical filter removes, from output light of the optical modulator, a frequency component in a range of ±fs/2 with respect to a center frequency of the modulated optical signal, and extracts at least a part of other frequency components. The delay circuit controls timings of the N drive signals so as to reduce optical power of the frequency component extracted by the optical filter.

Abstract: Systems are methods are provided for implementing an intelligent optical transceiver. The intelligent optical transceiver implements dynamic health monitoring and “time to fail” prediction functions to predict a failure of a component before it malfunctions during use. By employing the intelligent optical transceiver, a network can prevent failures in its optical connectivity that can degrade the network performance, such as experiencing outages and data unavailability. For example, the intelligent optical transceiver includes a module health monitor, which monitors, in real-time, health parameters of optical communication components in the intelligent optical transceiver. Also, the intelligent optical transceiver includes a time to fail predictor which predicts a time to fail for the optical communication components of the optical transceiver based on a result of a defined regression function.

Abstract: A safety supervision system for wireless power transmission, comprising a transmitter having an optical beam generator with safe states for transmitting power to receivers that convert the beam into electrical power. The system control unit stores previously known signatures categorized by predetermined parameters associated with one or more unwanted situations, stores data from sensors, compares this stored data to the signatures, and executes one or more responses based on this comparison. The system may comprise transmitter and/or receiver malfunction detection systems adapted to monitor the transmitter and receiver control units and to cause the optical beam generator to switch to a safe state upon detection of a transmitter or receiver control unit malfunction, and may further comprise a hazard detection system preventing human exposure to beam intensity above a predefined safe level.

Abstract: An on-chip adaptive optical receiver system, an optical chip, and a communication device are disclosed, which are applied to optical communication. The on-chip adaptive optical receiver system includes an antenna array configured for separating received spatial light to obtain a plurality of sub-light spots; an optical phased array configured for performing phase-shifting processing and beam combining processing on the sub-light spots to obtain combined light; and an optical receiving module configured for demultiplexing the combined light to obtain beacon light. The optical receiving module is further configured for detecting intensity information of the beacon light and generating a feedback signal according to the intensity information.

Abstract: A coherent passive optical network includes a downstream transceiver and first and second upstream transceivers in communication with an optical transport medium. The downstream transceiver includes a downstream processor for mapping a downstream data stream to a plurality of sub-bands, and a downstream transmitter for transmitting a downstream optical signal modulated with the plurality of sub-bands. The first upstream transceiver includes a first local oscillator (LO) for tuning a first LO center frequency to a first sub-band of the plurality of sub-bands, and a first downstream receiver for coherently detecting the downstream optical signal within the first sub-band. The second upstream transceiver includes a second downstream receiver configured for coherently detecting the downstream optical signal within a second sub-band of the plurality of sub-bands. The downstream processor dynamically allocates the first and second sub-bands to the first and second transceivers in the time and frequency domains.

Abstract: The disclosure provides a binary iterative clock synchronization system based on polarization entanglement GHZ state comprising a first synchronization party, a second synchronization party and an emitting party; the first synchronization party is connected with the second synchronization party through a classical channel, the emitting party is connected with the first synchronization party through a quantum channel, and the emitting party is connected with the second synchronization party through a quantum channel and a classical channel; the emitting party realizes the preparation of three-photon polarization entangled GHZ states and measures one of the photon polarization states; the first synchronization party and the second synchronization party perform measurement on the polarization states of the other two photons, and the second synchronization party and the emitting party compare the measurement results to obtain the measurement sequence information between the first synchronization party and the sec

Abstract: A wavelength debugging method of multi-channel optical module includes: determine the initial temperature of TEC, and plot the temperature-optical power curve of each channel; obtain temperature Tup and Tdown corresponding to upper and lower limit values of the target wavelength of each channel and the left and right security boundary temperatures Tleft? and Tright? of each channel; compare Tup, Tdown, Tleft?, Tright? of each channel, when the product is qualified, record the middle two values in descending order as T1 and T2, respectively; compare the size of T1 and T2 of each channel, when the product is qualified, take the maximum value of T1 of each channel as Tdown?, and take the minimum value of T2 of each channel as Tup?, the final setting temperature of TEC is calculated as T?=(Tdown?+Tup?)/2, and the corresponding wavelength for each channel at this temperature T? is the wavelength after debugging for each channel.

Abstract: Submarine cable branching units with fiber pair switching configured to allow any number of trunk cable fiber pairs to access the optical spectrum any number of branch cable fiber pairs. Access to a particular branch terminal is not limited to predefined subset of the trunk fiber pairs. This approach allows fewer branch cable fiber pairs to be equipped in each branching unit, reducing system cost, simplifies system planning and provides flexible routing of overall trunk cable capacity.