Abstract: A polarization change tracking apparatus, a processing apparatus for a received signal and methods thereof. The polarization change tracking method includes: estimating a polarization change speed in a link according to a received signal; setting a response coefficient of polarization tracking according to a relationship between an estimated polarization change speed and a predetermined value, to make a response of polarization tracking and a response of adaptive equalization be consecutive; and performing compensation for polarization change on the received signal according to a set response coefficient of polarization tracking.

Abstract: A method (100) for managing Optical Wireless Communication (OWC) in a User Equipment (UE) is disclosed, the UE being configured for Radio Frequency (RF) communication with a network and comprising at least two OWC receivers. The method comprises monitoring a captured luminous flux intensity at the OWC receivers (1 10) and, if a captured luminous flux intensity at at least one of the OWC receivers is above a viability threshold (120), selecting the OWC receiver having the highest captured luminous flux intensity (130) and extracting client data from an optical signal received on the selected OWC receiver (140). Also disclosed are a UE (300, 700) configured for RF communication with a network and for OWC, the UE comprising at least two OWC receivers, and a controller (500, 600) for managing OWC in a UE.

Abstract: A management system for an optical line system includes one or more processors and memory storing instructions that, when executed, cause the one or more processors to receive State of Polarization (SOP) measurements from one or more optical components in the optical line system, wherein the SOP measurements are taken while traffic-bearing channels are operating, and monitor health of one or more fibers based on the SOP measurements. The health can include detection and/or localization of SOP transients.

Abstract: Embodiments relate to providing simultaneous digital and analog services in optical fiber-based distributed radio frequency (RF) antenna systems (DASs), and related components and methods. A multiplex switch unit associated with a head-end unit of a DAS can be configured to receive a plurality of analog and digital downlink signals from one or more sources, such as a service matrix unit, and to assign each downlink signal to be transmitted to one or more remote units of the DAS. In one example, when two or more downlink signals are assigned to be transmitted to the same remote unit, a wave division multiplexer/demultiplexer associated with the multiplex switch unit can be configured to wave division multiplex the component downlink signals into a combined downlink signal for remote side transmission and to demultiplex received combined uplink signals into their component uplink signals for head-end side transmission.

Abstract: An edge wavelength-switching system includes an optical switch and a wavelength selective switch. The optical switch includes a west hub-side port, an east hub-side port, a west local-side port, and an east local-side port. The wavelength selective switch includes (i) a multiplexed port optically coupled to the west local-side port and (ii) a bypass port optically coupled to the east local-side port, and (iii) a plurality of demultiplexed ports. An optical network includes a network hub including an M-by-N1 wavelength-selective switch, N1>M?1, a first network node, and a second network node. Each of the first and second network nodes includes a respective edge wavelength-switching system. The network hub, the first network node, and the second network node are optically coupled.

Abstract: A system and method for ultrashort signal detection adds an optical weighting element upstream of a detector within a direct detection receiver. The optical weighting element is configured to generate an optical pulse that closely matches at least one ultrashort pulse within the input signal so that portions of the input signal that are nonoverlapping with the at least one ultrashort pulse are rejected.

Abstract: An optical network device includes a receiver that receives a polarization multiplexed optical signal and a processor. The processor separates an electric field information signal indicating the polarization multiplexed optical signal into first and second polarization components orthogonal to each other, generates third and fourth polarization components by controlling the first and second polarization components, calculates an evaluation value corresponding to a power of the third or fourth polarization component for each of a plurality of positions on a transmission line, calculates a variation in the evaluation value for a control amount for each of the plurality of positions, and decides whether a first position is a position to be detected based on a result of comparing a variation in an evaluation value for the first position with a variation in an evaluation value for a second position adjacent to the first position.

Abstract: An optoelectronic computing system includes a first semiconductor die having a photonic integrated circuit (PIC) and a second semiconductor die having an electronic integrated circuit (EIC). The PIC includes optical waveguides, in which input values are encoded on respective optical signals carried by the optical waveguides. The PIC includes an optical copying distribution network having optical splitters. The PIC includes an array of optoelectronic circuitry sections, each receiving an optical wave from one of the output ports of the optical copying distribution network, and each optoelectronic circuitry section includes: at least one photodetector detecting at least one optical wave from the optoelectronic operation. The EIC includes electrical input ports receiving respective electrical values.

Abstract: n wavelengths set such that delay differences between optical signals due to wavelength dispersion in an optical fiber between accommodation and base stations are at equal intervals are assigned to n antenna elements of the base station which are at predetermined intervals. The accommodation station adjusts the phases of optical signals of the wavelengths or modulated signals that modulate the optical signals such that the amounts of phase shift of their RF signals are at predetermined intervals. The accommodation station transmits beacon signals multiple times while varying a transmission phase shift interval ?1 and the terminal transmits beacon number information of a beacon signal selected based on received power multiple times.

Abstract: Embodiments of this application provide a method and an apparatus for obtaining optical distribution network (ODN) logical topology information, a device, and a storage medium. The method includes: obtaining identification information of each first ONU that is connected to a first passive optical network (PON) port and whose optical path changes and feature data of the first ONU in a first time window, where the feature data includes receive optical power and/or an alarm event; obtaining, based on the feature data of each first ONU, a feature vector corresponding to each first ONU; and performing cluster analysis on the feature vector corresponding to each first ONU, to obtain topology information corresponding to the first PON port. ONU topology information is obtained by analyzing an ONU feature.

Abstract: A transceiver device includes: a receiving device including a magnetic element having a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, wherein the receiving device is configured to receive an optical signal; a transmission device including a modulated light output element, wherein the transmission device is configured to transmit an optical signal; and a circuit chip including an integrated circuit electrically connected to the magnetic element and the modulated light output element.

Abstract: An optical module includes: a first board having an optical component bonded thereto with an adhesive; a connection structure part rising from the first board and made of a material having lower thermal conductivity than thermal conductivity of a material of the first board; and a second board joined to the connection structure part.

Abstract: Methods for estimating the Effective Modal Bandwidth (EMB) of laser optimized Multimode Fiber (MMF) at a specified wavelength, ?S, based on the measured EMB at a first reference measurement wavelength, ?M. In these methods the Differential Mode Delay (DMD) of a MMF is measured and the Effective Modal Bandwidth (EMB) is computed at a first measurement wavelength. By extracting signal features such as centroids, peak power, pulse widths, and skews, as described in this disclosure, the EMB can be estimated at a second specified wavelength with different degrees of accuracy. The first method estimates the EMB at the second specified wavelength based on measurements at the reference wavelength. The second method predicts if the EMB at the second specified wavelength is equal or greater than a specified bandwidth limit.

Abstract: Probabilistic constellation shaping (PCS) is applied to a desired probability distribution over the 2-D constellation points. Constellation points are partitioned into multiple disjoint sets in which all the constellation points within a subset have the same energy level (i.e., amplitude) or distance from the origin on the complex plane. Each of the sets may be further subdivided into smaller disjoint sets of constellation points to facilitate labeling of the constellation points. The sets may be indexed from 0 to the total number of disjoint sets to form an index set. The desired distribution may then be applied over the index set either using a distribution matcher (DM) or using a lookup table. The desired distribution may be generated before forward error correction (FEC) encoding that preserves the generated amplitude distribution through FEC encoding of data bits.

Abstract: An optronic system (100) for a countermeasure unit (10) to optically communicate with another communication terminal is disclosed. The countermeasure unit (10) comprises a laser beam source (12) and a directing device (14) for a laser beam (15) of the laser beam source (12) and is configured to dazzle or to jam an object of threat (50). The optronic system (100) comprising: a detector (110), a modulation unit (120), and a control unit (130). The detector (110) is configured to detect an incoming communication in an incoming signal (25). The modulation unit (120) is configured to demodulate the incoming signal (25) or cause a modulation of an outgoing laser beam (15). The control unit (130) is configured, in response to the detected incoming communication, to control the modulation unit (120) to demodulate the incoming signal (25) or to modulate the outgoing laser beam (15) to enable an optical communication via the laser beam source (12) of the countermeasure unit (10).

Abstract: A method (100) of encoding communications traffic bits onto an optical carrier signal in a pulse amplitude modulation, PAM, format. The method comprises: receiving (102) bits to be transmitted; receiving (104) an optical carrier signal comprising optical pulses having an amplitude and respective phases; performing (106) PAM of the optical pulses to encode at least one respective bit in one of a pre-set plurality of amplitudes of a said optical pulse; and performing (108) phase modulation of the optical pulses to encode at least one further respective bit in a phase difference between a said optical pulse and a consecutive optical pulse.

Abstract: An optical transceiver is configured to receive an optical signal on which a monitoring signal encoded by Manchester encoding is superimposed. The optical transceiver includes a decoding circuit configured to decode the monitoring signal from an electrical signal generated from the optical signal. The decoding circuit includes an interval measuring unit and a decoding unit. The interval measuring unit is configured to detect only a rising edge or a falling edge of a waveform of the electrical signal, to measure a first time interval between a detected first edge and a second edge detected immediately after detecting the first edge, and to measure a second time interval between the second edge and a third edge detected immediately after detecting the second edge. The decoding unit is configured to decode the monitoring signal encoded by the Manchester encoding based on a ratio between the first and second time intervals.

Abstract: Systems of enhancing contrast of lighting can include a light-transmitting subsystem having a light source to emit a stream or light-signal pulses and an encoding circularly polarizing filter to optically encode the stream of light-signal pulses with circular polarization, and a light-receiving subsystem including a decoding circularly polarizing filter to optically decode the circular polarization of the stream of light-signal pulses and a light imager to receive the stream of light-signal pulses after being optically decoded by the decoding circularly polarizing filter. In another example, the system can include a polarimetric light imaging assembly, a light source to generate a stream of light-signal pulses directed at the polarimetric light imaging assembly, and a control system to synchronously control the light-signal pulses to be emitted from the light source in timed correlation with a component(s) of the polarimetric light imaging assembly.

Abstract: Systems and methods include receiving a plurality of symbols that are part of a defined Digital Signal Processing (DSP) frame for coherent optical communication, wherein the DSP frame structure has a messaging channel incorporated therein that includes a subset of the plurality of symbols; capturing multiple samples of the messaging channel; and determining a message in the messaging channel based on analysis of the multiple samples. The method can further include transmitting, in the messaging channel, a reply to the message with the reply being repeated multiple times. The analysis is performed prior to Forward Error Correction (FEC) decoding on the data path.

Abstract: A digital receiver is configured to process a polarization multiplexed carrier from a communication network. The polarization multiplexed carrier includes a first polarization and a second polarization. The receiver includes a first lane for transporting a first input signal of the first polarization, a second lane for transporting a second input signal of the second polarization, a dynamic phase noise estimation unit disposed within the first lane and configured to determine a phase noise estimate of the first input signal, a first carrier phase recovery portion configured to remove carrier phase noise from the first polarization based on a combination of the first input signal and a function of the determined phase noise estimate, and a second carrier phase recovery portion configured to remove carrier phase noise from the second polarization based on a combination of the second input signal and the function of the determined phase noise estimate.