Abstract: A branch ratio calculation method in an optical communication system constituting a tree-structured network in which a first communication device is used as a root node, a plurality of optical splitters are used as intermediate nodes, and a plurality of second communication devices are used as leaf nodes, the method including a calculation step of calculating branch ratios of the plurality of optical splitters based on a length of a transmission path between the first communication device and the optical fiber in order from a hierarchy of the tree-structured network so that the second communication device receives light transmitted by the first communication device at a target intensity.

Abstract: An optical communication system includes a first optical communication device; a plurality of second optical communication devices configured to perform communication with the first optical communication device; a chromatic dispersion compensation device connected to the first optical communication device; and an optical transmission line connected to the chromatic dispersion compensation device, a path of the optical transmission line connected to the chromatic dispersion compensation device being split into a plurality of paths at a branch point, the resulting paths being respectively connected to the plurality of second optical communication devices, and the optical transmission line being configured to transmit optical signals through the paths, in which the chromatic dispersion compensation device includes a chromatic dispersion compensator configured to perform chromatic dispersion compensation corresponding to amounts of chromatic dispersion generated in optical signals propagated through respective pa

Abstract: In an optical receiver apparatus for use with multiple optical modulation techniques, a photodiode circuit is configured to process optical signals corresponding to multiple optical modulation techniques, including a first modulation technique and a second modulation technique different from the first modulation technique. The photodiode circuit includes: a first photodiode configured to receive a first optical signal corresponding to a first modulation technique, and a multiple-input second photodiode coupled in series with the first photodiode. The multiple-input second photodiode is configured to receive i) a second optical signal corresponding to the first modulation technique, and ii) a third optical signal corresponding to the second modulation technique. An input of a transimpedance amplifier is coupled to the first photodiode and the second photodiode via a node between the first photodiode and the second photodiode.

Abstract: Systems, computer program products, and methods are described herein for network discovery, port identification, and/or identifying fiber link failures in an optical network, in accordance with an embodiment of the invention. The present invention may be configured to sequentially connect each port of an optical switch to a network port of a server and generate, based on information associated with network devices connected to the ports, a network map. The network map may identify which network devices are connected to which ports of the optical switch and may permit dynamic port mapping for network installation, upgrades, repairs, and/or the like. The present invention may also be configured to determine a fiber link in which a failure occurred and reconfigure the optical switch to allow communication between an optical time-domain reflectometer and the fiber link to test the fiber link.

Abstract: Mixing between I and Q components in coherent homodyne optical signals can occur due to phase shifts, e.g. relative to the local oscillator, relative to the other signal components. In some examples, the phase shifts can arise due to thermal expansion of the optical waveguides and/or can include polarization mixing. A descrambler functions to correct for mixing between multiple signal components. The descrambler may be configured to at least partially correct for a phase difference between a first plurality of modulated optical data signals and a first local oscillator reference signal; and a controller may be configured for determining a first correction parameter for at least partially correcting for the phase difference, and for transmitting the first correction parameter to the descrambler. The controller may be configured for determining the first correction parameter from a first pilot signal transmitted with the first plurality of modulated optical data signals.

Abstract: One embodiment is a method that includes generating a request for a data item in a memory, obtaining the data item from the memory with a photonic interface, sending the data item to a fabric using a transmit unit of the photonic interface, and routing the data item through a portion of the fabric coupled to the memory, the portion of the fabric including one or more additional transmit and receive units between the photonic interface and a destination receive unit.

Abstract: Techniques for repairing a network failure in a Passive Optical Network (PON) include establishing a communication session with an optical network terminal (ONT) in a PON via a short-range communication link. In response to establishing the communication session, the techniques include receiving diagnostic information related to a network failure corresponding to the ONT, and presenting the diagnostic information to a user for the user to repair the ONT based on the received diagnostic information.

Abstract: Disclosed are an ONU migration detection method, OLT, ONU and storage medium. The ONU migration detection method may include: receiving first identification information from an ONU, the first identification information is configured to uniquely identify a historical position accessed by the ONU; acquiring second identification information according to a current position of the ONU, the second identification information is configured to uniquely identify the current position; and comparing the first identification information with the second identification information, and determining that ONU migration occurs in response to the first identification information being mismatched with the second identification information.

Abstract: An optical line terminal (OLT) in flexible passive optical network (PON) transmits a downstream signal with two or more modulation formats, wherein at least one of the modulation formats is a modified PAMx modulation format and wherein x is greater than 2. The modified PAMx modulation encodes data bits such that the probability of at least one predetermined transition between amplitude levels is modified. Furthermore, an optical network unit (ONU) in the flexible PON is assigned to one of the plurality of modulation formats based on one or more parameters, such as configuration of the ONU and line conditions.

Abstract: In some examples, OTDR event detection and light power level measurement-based fiber optic link certification may include performing, at one end of a device under test (DUT) of a network, a light power level measurement. An OTDR measurement may be performed at the one end of the DUT to detect at least one event associated with the DUT. Based on analysis of the light power level measurement and the OTDR measurement, an event classification may be generated to classify the at least one event associated with the DUT.

Abstract: This application discloses a signal generating method, apparatus, and system. One example method includes: performing cyclic electro-optic modulation on a first signal to generate a first optical frequency comb signal, where the first signal is a signal output by a laser source, the first optical frequency comb signal includes a target spectral component, and a frequency of the target spectral component is equal to a sum of or a difference between a frequency of the first signal and a frequency of a target signal; performing first filtering processing on the first optical frequency comb signal to generate the target spectral component; and generating the target signal based on a heterodyne beat frequency of the first signal and the target spectral component.

Abstract: The present disclosure provides an information transmission method, an information transmission device, a communication device and a readable storage medium. The information transmission method includes: obtaining OAM information from an optical network; encapsulating the obtained OAM information to form an OAM frame, the OAM frame including N data frames each having a frame length of L, N varying along with a volume of the OAM information, L being a constant value regardless of the volume of the OAM information; and transmitting the OAM frame. The OAM information is transmitted in a length-constant frame, so it is able to facilitate encoding and decoding of a message, simplifying the processing and reduce the time consumption, and facilitate the extension in accordance with a message content and ensure the extendibility, thereby to solve such problems as complicated processing, being time-consuming, and poor extendibility in the conventional OAM information transmission scheme.

Abstract: An optical assembly is used for communicating laser light from a plurality of laser sources into channels for an optical network. The optical assembly comprises an optical substrate, an input optic, at least one Z-block, filters, at least one fiber collimator, and at least one delivery fiber. The input optic is disposed on the optical substrate and is configured to receive the laser light from the laser sources. The input optic is configured to collimate the laser light into a plurality of collimated laser beams. The at least one Z-block is disposed on the substrate and has an input surface and an output surface. The input surface has a plurality of filters disposed thereon, and the input surface is disposed at an angle of incidence relative to the collimated beams from the input optic. The output surface is disposed parallel to the input surface and can have at least one isolator.

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: For an optical monitor device that detects the intensity of light propagating through an optical fiber, a reduction in size and cost of the optical monitor device are to be achieved.

Abstract: Electro-photonic integrated circuits comprising optical transmitters and receivers are disclosed, wherein a monolithically integrated electro-absorption modulated laser (EML) is operable bidirectionally, in a transmitter mode and in a receiver mode. Vertically stacked waveguides are provided for a laser and an electro-absorption modulator (EAM). The laser and EAM are optically coupled using a laterally tapered vertical optical coupler. The EML comprises monolithically integrated electronic circuitry, e.g., driver and control electronics for the driving the laser and EAM as an EML, in transmitter mode. The electronic circuitry comprises a transimpedance amplifier (TIA). The EAM has first and second parts that can be independently biased. In receiver mode, the laser current is reduced to close to the threshold, and a first part of the EAM is biased to absorb residual laser light, and the second part of the EAM acts as a photodiode receiver to provide a photocurrent to the TIA.

Abstract: A computer-implemented method of transmitting through a disordered medium from a transmitter to a receiver an image represented as input coherent electromagnetic radiation, the disordered medium having a transmission matrix comprising a plurality of complex-valued transmission constants that relate said input coherent electromagnetic radiation to output electromagnetic radiation at said receiver, which method comprises the steps of: performing a characterising process on said disordered medium to determine said transmission matrix; using said transmitter to transmit said image through said disordered medium; performing a reconstruction process using said transmission matrix to generate a reconstructed image from the output electromagnetic radiation at said receiver; wherein in said characterisation process the step of determining said transmission matrix comprises: determining said complex-valued transmission constants as real-valued transmission constants by using an approximately linear relationship bet

Abstract: The optical communication system includes the optical distribution device (100) provided between the wavelength routing device (30) and the optical multiplexing/demultiplexing device (40). The wavelength routing device outputs the optical signal input from the port on the wavelength variable subscriber device side to the port uniquely determined by a combination of the wavelength of the optical signal and the port to which the optical signal is inputted. The wavelength variable subscriber device can execute the first protection for switching the wavelength of the optical signal to be transmitted and received to the spare wavelength different from the operating wavelength when the wavelength variable subscriber device and the wavelength variable communication device (10) are disconnected.

Abstract: A passive optical network system having a node that is optically coupled to optical line terminals (OLTs), and that is optically coupled to optical network units (ONUs). The node includes at least one fiber link module (FLM), each FLM including an upstream multiplex conversion device (MCD), and a downstream MCD. The upstream MCD receives an upstream optical signal from the ONUs, converts the upstream optical signal to an upstream electrical signal, and transmits a regenerated upstream optical signal to the OLTs. The downstream MCD receives a downstream optical signal from the OLTs, converts the downstream optical signal to a downstream electrical signal, and transmits a regenerated downstream optical signal to the ONUs.

Abstract: A single-fiber bidirectional optical ring system includes: a central station; slave stations; and a network which connects the central station and the slave stations in a ring shape by optical fibers.