Abstract: A wearable device includes a frame and a magnetic coupler opening formed in the frame. Wearable device further includes a processor, a memory accessible to the processor, and a very high frequency (VHF) radio transceiver for data transmission and reception and connected to the processor. Wearable device further includes a magnetic coupler connected to the VHF radio transceiver. Magnetic coupler includes a diamagnetic material shaped to form a VHF transmission or reception terminal that partially or fully aligns with the magnetic coupler opening. During transmission, magnetic coupler is configured to radiate transmitted VHF band radio modulated signals into tissue of the user. During reception, magnetic coupler is configured to absorb received VHF band radio modulated signals from the tissue of the user.

Abstract: A reconfigurable server includes improved bandwidth connection to adjacent servers and allows for improved access to near-memory storage and for an improved ability to provision resources for an adjacent server. The server includes processor array and a near-memory accelerator module that includes near-memory and the near-memory accelerator module helps provide sufficient bandwidth between the processor array and near-memory. A hardware plane module can be used to provide additional bandwidth and interconnectivity between adjacent servers and/or adjacent switches.

Abstract: A docking station comprises a computing unit and a charging system connected via a data connection. The charging system has a first charging coil in a housing such that a battery of a mobile device can be charged by a second charging coil while at the same time data can be transferred between the mobile device and the computing unit and to at least one peripheral device, whereby an increased protection against eavesdropping results without the use of additional devices. This is achieved in that the first and second charging coils are designed and connected such that the charging coils are actuated by the computing unit and by a mobile device electronic system such that data to be transferred is transmitted between the mobile device and the docking station via alternating fields, which are generated and received in the first and second charging coils, in the near-field region in an interference-free and eavesdropping-secured manner.

Abstract: A method for locating a field device having a wireless interface is provided, the method including the following steps: transmitting, from the field device, identification information including distance information and direction information; receiving, by an operator device, the identification information; and displaying, by the operator device, based on the identification information, a distance, and a direction of the field device with respect to the operator device.

Abstract: Embodiments are disclosed for reduced lane utilization for an optical transceiver. An example optical transceiver apparatus includes at least one optical source and an optical connector. The at least one optical source is attached to a printed circuit board (PCB) and is configured to facilitate communication of optical signals. The PCB comprises an electrical connector electrically connected to the at least one optical source and is configured to facilitate communication of electrical signals. Furthermore, the PCB is attached to a mechanical structure. The optical connector is attached to the mechanical structure and is coupled to the at least one optical source via at least one optical fiber that facilitates transmission of the optical signals.

Abstract: The present invention relates to the technical field of optical communications, and particularly relates to a wavelength locking optical module, a device, and a wavelength locking method. The optical module comprises a DSP unit, a TOSA, and a ROSA. The DSP unit has a signal output terminal connected to the TOSA and a signal input terminal connected to the ROSA. A TEC is provided within the TOSA, and is used to adjust a temperature according to a control signal sent from the DSP unit and accordingly adjust a emission wavelength of the TOSA. An optical filter is provided within the ROSA and used to filter a wave, such that light having a pre-determined wavelength passes through the filter and is converted into an electrical signal and output to the DSP unit. The DSP unit calculates an optical power according to the received electrical signal, and determines wavelength control of the TOSA according to an optical power change.

Abstract: An optical communication system including a hub optical transceiver, a power splitter, and a plurality of spoke transceivers. The hub optical transceiver is configured for receiving a spectrum of wavelengths. The power splitter is coupled to the hub optical transceiver, and operates as a passive device that is configured to replicate the spectrum of wavelengths and output a plurality of replicated spectrum of wavelengths, and each replicated spectrum of wavelengths has a corresponding power that is a fraction of a total power received from the hub optical transceiver. The plurality of spoke transceivers is coupled to the power splitter and each of the plurality of spoke transceivers is configured to receive a corresponding one of the plurality of replicated spectrum of wavelengths, wherein each spoke transceiver is tunable to select a band of wavelengths that set a bandwidth for the each spoke transceiver.

Abstract: A control system includes a phase shift unit configured to provide a phase difference between a first switching clock signal and a second switching clock signal, a power transmission coil, a switching circuit configured to switch an input voltage based on the first switching clock signal and apply the switched voltage to the power transmission coil, a power reception coil configured to receive electric power output from the power transmission coil by electromagnetic field coupling, a wireless transmission unit configured to wirelessly transmit the second switching clock signal and output a third switching clock signal, and a rectifier circuit configured to rectify a voltage input from the power reception coil by switching the voltage based on the third switching clock signal and apply the rectified voltage to a load. A voltage input from the power reception coil to the rectifier circuit and the third switching clock signal have different phases.

Abstract: A test instrument for providing an optics troubleshooting technique of an optical transceiver is disclosed. The test instrument may comprise a processor and a memory, which when executed by the processor, performs the optics troubleshooting technique. The optics troubleshooting technique may include identifying a test signal from the optical transceiver. The optics troubleshooting technique may include determining signal power associated with the signal. The optics troubleshooting technique may further include applying one or more expert mode settings. In some examples, the one or more expert mode settings may be applied in a predefined order until an acceptable BER result is achieved over a predefined test period. In this way, test instrument may determine which of the one or more expert mode settings is responsible for the acceptable BER result.

Abstract: An RF transmitter comprising an optical source configured to generate a pair of optical lines separated by an RF carrier frequency. The transmitter may comprise a graphene photodetector having at least two electrical contacts; a transmit antenna coupled to a first of the electrical contacts; and an electrical data signal input connected to a second of the electrical contacts. The graphene photodetector is illuminated by the optical source; it may comprise a graphene photo-thermal effect (PTE) photodetector or a bolometric photodetector. A corresponding receiver is also described.

Abstract: A co-packaged optical-electrical chip can include an application-specific integrated circuit (ASIC) and a plurality of optical modules, such as optical transceivers. The ASIC and each of the optical modules can exchange electrical signaling via integrated electrical paths. The ASIC can include Ethernet switch, error correction, bit-to-symbol mapping/demapping, and digital signal processing circuits to pre-compensate and post-compensate channel impairments (e.g., inter-channel/intra-channel impairments) in electrical and optical domains. The co-packaged inter-chip interface can be scaled to handle different data rates using spectral efficient signaling formats (e.g., QAM-64, PAM-8) without adding additional data lines to a given design and without significantly increasing the power consumption of the design.

Abstract: A wearable device includes a frame and a magnetic coupler opening formed in the frame. Wearable device further includes a processor, a memory accessible to the processor, and a very high frequency (VHF) radio transceiver for data transmission and reception and connected to the processor. Wearable device further includes a magnetic coupler connected to the VHF radio transceiver. Magnetic coupler includes a diamagnetic material shaped to form a VHF transmission or reception terminal that partially or fully aligns with the magnetic coupler opening. During transmission, magnetic coupler is configured to radiate transmitted VHF band radio modulated signals into tissue of the user. During reception, magnetic coupler is configured to absorb received VHF band radio modulated signals from the tissue of the user.

Abstract: An embodiment relates to the transmission of a data set to a central data store. A data set is received via a data source. Furthermore, country information is optionally received via the data source. Furthermore, a data classification is determined based on the data set via the data source. Furthermore, the data classification and optionally the country information are sent to a server via the data source. Furthermore, data transmission information from the server is received via the data source. In this context, the data transmission information is based on the data classification and optionally on the country information and the data transmission information relates to the permissibility of the transmission of the data set. Furthermore, the data set is transmitted to the central data store in dependence on the data transmission information.

Abstract: An optical transceiver includes a housing, a mother board, an optical communication module and a daughter board. The mother board is accommodated in the housing. The optical communication module is disposed on a top surface of the mother board, and the optical communication module includes a first electrical interface. The daughter board is disposed on the top surface of the mother board, and the daughter board includes a second electrical interface electrically connected with the first electrical interface. The optical communication module is disposed on a flat region of the top surface of the mother board.

Abstract: A laser package is mounted on the printed circuit board. At least one thermal via extends through the printed circuit board, coupled to the laser package. A thermal bridge is coupled to the at least one thermal via on the bottom of the printed circuit board. A thermal paste connects the thermal bridge to a conductive ground plane on the bottom of the printed circuit board, and to a mechanical housing.

Abstract: An example tracking signal device comprises a housing and a light source disposed within the housing. A window is defined within the housing optically downstream of the light source. The device further comprises a sensor configured to receive a first beam of radiation and a controller operably coupled to (i) the light source and (ii) the sensor. The controller is configured to control the light source to emit a second beam of radiation based at least in part on receipt of the first beam of radiation by the sensor.

Abstract: An optical module includes an interface electrically connected to an external device to receive a data signal to be transmitted, a signal processor configured to perform serialization and signal modulation on the received data signal, an optical transceiver configured to generate an optical transmission signal by receiving a direct current (DC) light source, in which a plurality of light sources having different wavelengths are multiplexed, from an optical power supply and performing optical modulation thereon through the serialized and modulated data signal, and an optical fiber connector configured to output the generated optical transmission signal to the external device and receive an optical reception signal from the external device.

Abstract: An integrated transceiver chip comprising: a plurality of bidirectional ports; a plurality of grating couplers; a receiver having a first and a second input ports, the first input port being optically connected to a first grating coupler of the plurality of grating couplers, and the second input port being optically connected to a first bidirectional port of the plurality of bidirectional ports; and a transmitter having a first and a second input and a first and a second output ports, the first input port being optically connected to a second bidirectional port of the plurality of bidirectional ports and the second input port being optically connected to a second grating coupler, and the first output port being optically connected to a third bidirectional port of the plurality of bidirectional ports and the second output port being optically connected to a third grating coupler of the plurality of grating couplers.

Abstract: A passive optical network device comprising a casing, printed circuit board, and fiber optic transceiver system is provided. The fiber optic transceiver system comprises a fiber optic components device, fiber optic transceiver, and RF connector. During operation, the fiber optic components device converts optical signals from the fiber optic transceiver to digital signals, and then transmits the converted digital signals to external electronic systems via the hot-pluggable transceiver connection interface. The fiber optic components device converts digital signals from the external electronic systems to optical signals, and then transmits the optical signals to other external electronic systems via the fiber optic transceiver. The RF connector transmits RF signals from additional external electronic systems to the external electronic systems via the hot-pluggable transceiver connection interface.

Abstract: An integrated circuit (IC) die is disclosed. The IC die can include a signal via extending through the IC die. The IC die can include a transmission line extending laterally within the IC die in a direction non-parallel to the signal via, the transmission line configured to transfer an electrical signal to the signal via. The IC die can include a matching circuit disposed between the transmission line and the signal via. The matching circuit can include inductance and capacitance matching circuitry to compensate for parasitic inductance and capacitance introduced by transition from the IC die to an underlying carrier.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for clock synchronizing an optical system and multiple leaf systems. In some implementations, a method includes: first data is received from an optical system. The first data is detected using a local oscillator signal provided by a local oscillator laser. The first data is processed using a first sampling rate. A frequency of a clock signal supplied by a reference clock is adjusted based on the processed first data. Second data is transmitted to the optical system at a rate based on the clock signal.

Abstract: Disclosed are an impedance correcting method and apparatus, and an impedance-corrected signal line for an optical transceiver. The impedance correction method includes receiving an impedance according to an error of a resin applying process of a signal line for an optical transceiver, acquiring a correction parameter for generating a correction impedance based on the impedance according to the error, and determining the correction impedance for correcting the impedance according to the error based on the correction parameter.

Abstract: A criterion method of GCCS (Globally Complete Chaos Synchronization) for three-node VCSEL (Vertical Cavity Surface Emitting Laser) networks with delay coupling is provided, including steps of: providing a delay-coupled VCSEL network consisting of three identical units and dynamic equations of the VCSEL network; providing assumptions of an outer-coupling matrix and a unitary matrix under the dynamic equations of the VCSEL network; in the three-node VCSEL network, determining rate equations of i-VCSEL, determining dynamic equations of a synchronization manifold, and determining a master-stability equation; calculating three maximum Lyapunov exponents; determining a stability of a synchronization state of the three-node VCSEL network, and determining whether the synchronization manifold of the VCSEL network is a chaotic waveform.

Abstract: One example optical transceiver includes an optical interface, an optical receiver, and a polarization-maintaining optical waveguide, where the optical receiver includes a mixer, an optical-to-electrical converter, an analog-to-digital converter, and a digital signal processor.

Abstract: Provided are a repeater device for a DisplayPort side channel and an operating method thereof. The repeater device of a DisplayPort includes: a source device processor transmits or receives an electrical signal of a side channel data of the display port to or from a source device and processes repeater data; and a sink device processor transmits or receives an electrical signal of a side channel data of the display port to or from a sink device and processes repeater data, wherein the source device processor or the sink device processor comprising a controller processes repeating of the side channel data of the display port using the repeater data which is obtained by transforming the electrical signal to an optical signal.

Abstract: Systems, methods, and devices are described for in-situ testing of vertical-cavity surface-emitting lasers (VCSELs), VCSEL arrays or laser diodes (each a laser). Testing may comprise bias voltage measurements of one or more lasers. Embodiments may comprise one of a laser, a driver circuit providing a bipolar drive to the laser, and a sensing circuit to measure and/or monitor damage or degradation of the laser. The bipolar drive may comprise a pulsed forward bias output configured to produce a light output during an on-time of the laser, and a pulsed reverse bias output during an off-time of the pulsed forward bias output. The pulsed outputs may comprise a variable, chirped frequency. One or more of a reverse leakage current, and a junction temperature may be measured to monitor a state of health of the laser.

Abstract: There is provided an optical communication device capable of minimum suppressing inter-signal interference of inductors mounted to enable a transmission signal to be transmitted and received with a high frequency. The optical communication device comprises a sub-package as a subassembly in each of a plurality of signal channels. The sub-package includes a substrate on which an optical semiconductor and an IC are flip-chip connected. The optical semiconductor includes a pair of photodiodes receiving a differential optical signal and outputting a differential current signal. The IC includes a transimpedance amplifier converting the differential current signal from the optical semiconductor to a voltage signal. The optical semiconductor has a pair of inductors formed for each of the pair of photodiodes and a ground wiring formed so as to surround the formed pair of inductors.

Abstract: Light is modulated at a source to encode data. An additional tracking signal is imposed on the light using polarization modulation (PM). PM modulates one or more values of polarization rotation or polarization ellipticity of the light. These values may be dithered within constraints to provide a specified modulation index at the optical receiver, without impairing the encoded data. At the optical receiver, a polarization analyzer is used to recover the tracking signal, converting the polarization modulation to amplitude modulation. For example, after the light passes through the analyzer, an array of optical photodetectors detects the changes in apparent intensity resulting in the interaction between the light and the analyzer that correspond to the tracking signal. Due to a high modulation index, the recovered signal exhibits a high signal to noise ratio (SNR). The high SNR improves a noise equivalent angle, improving tracking performance.

Abstract: A lighting system includes a plurality of lighting devices installed in a predetermined space and connected to one another to communicate with one another using at least one of a first communication method and a second communication method, and a mobile device directly connected to at least one of the plurality of lighting devices to communicate therewith according to the first communication method. The first communication method and the second communication method are different. Each of the plurality of lighting devices includes a communication module configured to support the first communication method and the second communication method, and a driver configured to drive a light source in response to a control command received by the communication module.

Abstract: A reception device includes: an image sensor that captures an image, and a reception unit configured to sample a plurality of pixels included in each of N (N being an integer greater than or equal to two) regions included in an imaging surface of the image sensor to receive, in parallel, N mutually different optical signals transmitted from a plurality of light sources.

Abstract: An optical transceiver includes a housing, a heat dissipation module and an optical communication module. The heat dissipation module includes a first heat conductive component and a second heat conductive component accommodated in the housing. The first heat conductive component and the second heat conductive component are two independent components, and the first heat conductive component thermally contacts the second heat conductive component. The optical communication module is accommodated in the housing and thermally contacts the heat dissipation module.

Abstract: Optical networks, transponders and single-laser coherent transceiver are described. The single-laser coherent transceiver includes a wavelength source, a transmitter and a receiver. The wavelength source is tuned to supply a first optical signal having a first wavelength. The transmitter receives the first optical signal and encodes client data into the first optical signal to generate a second optical signal. The receiver receives the first optical signal from the wavelength source and a fraction of the second optical signal.

Abstract: The present invention reduces the risk of damaging a waveguide made of a brittle material. A transmission line (1) includes: a first waveguide (11) which is made of a brittle material; a second waveguide (21); and a bonding layer (31) by which the first waveguide (11) and the second waveguide (21) are bonded and which is electrically conductive. At least part of the bonding layer (31) is made of an electrically conductive adhesive, the at least part of the bonding layer (31) being in contact with the first waveguide (11).

Abstract: A wearable device includes a frame and a magnetic coupler opening formed in the frame. Wearable device further includes a processor, a memory accessible to the processor, and a very high frequency (VHF) radio transceiver for data transmission and reception and connected to the processor. Wearable device further includes a magnetic coupler connected to the VHF radio transceiver. Magnetic coupler includes a diamagnetic material shaped to form a VHF transmission or reception terminal that partially or fully aligns with the magnetic coupler opening. During transmission, magnetic coupler is configured to radiate transmitted VHF band radio modulated signals into tissue of the user. During reception, magnetic coupler is configured to absorb received VHF band radio modulated signals from the tissue of the user.

Abstract: An optical transceiver monitoring system includes an optical transceiver device that includes a non-volatile memory system, and a computing device that includes a computing device port that is coupled to the optical transceiver device. The computing device monitors the computing device port and, in response, detects one or more interactions between the optical transceiver device and the computing device. The computing device determines that the one or more interactions satisfy an event condition, and in response to the one or more interactions satisfying the event condition, provides first event information that corresponds to the one or more interactions to the optical transceiver device for storage in the non-volatile memory system.

Abstract: A reconfigurable server includes improved bandwidth connection to adjacent servers and allows for improved access to near-memory storage and for an improved ability to provision resources for an adjacent server. The server includes processor array and a near-memory accelerator module that includes near-memory and the near-memory accelerator module helps provide sufficient bandwidth between the processor array and near-memory. A hardware plane module can be used to provide additional bandwidth and interconnectivity between adjacent servers and/or adjacent switches.

Abstract: A pluggable optical module includes one or more optical interfaces; an interface for electrically connecting to a host device; and a processor configured to, subsequent to insertion of the pluggable optical module in a host device and performance of a first stage of boot loader, execute an early management interface handler that supports access to management memory on the pluggable optical module by the host device, and continue a boot process of the pluggable optical module including loading an operating system and application software for control and management of the pluggable optical module, wherein the early management interface handler supports queries and provisioning requests from the host device while the boot process is performed. The early management interface handler is loaded after insertion, within less time than required by the full boot process.

Abstract: Provided is an in-store dual-mode communication system in which shelves are disposed within a commercial space. A server is coupled to the Internet and/or a wide-area network and is configured to send and receive communications. Also provided are light-based messaging units that are located on and/or attached to such shelves, each: 1) having a light source, 2) receiving a communication from the server, and 3) in response to receipt of such communication, turning the light source on and off so as to broadcast a digital message that was included within such communication, as a binary-encoded digital signal corresponding to on/off states of the light source. A user device: (i) receives, via its light sensor, and then decodes the binary-encoded digital signal from a light-based messaging unit in order to obtain the digital message that corresponds to it; and also (ii) communicates with the server via its wireless interface.

Abstract: A continuously adjustable optical beam splitter includes a circular to linear polarization converter, a polarization rotator, and a polarization beam splitter that apportions light between two outputs. The polarization converter can include a quarter wave plate. The polarization rotator can include a mechanically rotated half wave plate or an electronically controlled liquid crystal variable retarder. The light source can be astronomical, reflected LIDAR light, or a laser beam from a remote laser communication node. Also disclosed is a free space laser communication terminal that implements the disclosed optical beam splitter, wherein the optical beam splitter diverts substantially all received laser light to an alignment channel during initial alignment, and then during message communication diverts more than 90%, and in embodiments up to 98%, of the received light to a communication channel, while alignment is maintained by continuing to divert the remaining laser light to the alignment channel.

Abstract: A test instrument for providing an optics troubleshooting technique of an optical transceiver is disclosed. The test instrument may comprise a processor and a memory, which when executed by the processor, performs the optics troubleshooting technique. The optics troubleshooting technique may include identifying a test signal from the optical transceiver. The optics troubleshooting technique may include determining signal power associated with the signal. The optics troubleshooting technique may further include applying one or more expert mode settings. In some examples, the one or more expert mode settings may be applied in a predefined order until an acceptable BER result is achieved over a predefined test period. In this way, test instrument may determine which of the one or more expert mode settings is responsible for the acceptable BER result.

Abstract: The present invention relates to an all-in-one converter using a low-speed optical module on a high-speed switch. The present invention relates to the field of optical modules in optical communications. It provides a solution of using a 25G optical module on a 100G switch, and simultaneously enabling a 10G optical module to be used on a 40G switch. A first electrical interface of the converter is connected with a 100G/40G switch, which meets the requirements of SFF-8636 protocol and realizes the bidirectional transmission of signals from the switch to the converter. A second electrical interface of the converter is connected with the optical module, which realizes the module's bidirectional transmission from the converter to the optical module. There is a signal conversion circuit inside the converter, which makes the signals of the two electrical interfaces meet the requirements of their respective protocols.

Abstract: Disclosed is an electronic device including a housing, a printed circuit board (PCB) in the housing, wherein the PCB includes a plurality of layers with one or more conductive and insulation layers, a first electrical component formed as at least a part of or in the housing, a second electrical component above or near the PCB in the housing, wherein the first and second electrical components are separated, and at least one electrical path extending from the first electrical component to the second electrical component, wherein at least a portion of the electrical path runs on or inside the PCB, wherein the PCB includes a region including a pattern of conductive vias, wherein each of the vias extends through at least part of the plurality of layers to contact at least one of the one or more conductive layers, and wherein the electrical path runs through the region without contacting the vias.

Abstract: A method of using an adjustable attenuation fiber optic wrap plug (“AAFOWP”) includes receiving initial data into a wireless module of the AAFOWP, wherein the initial data corresponds to an initial desired attenuation level that the first AAFOWP is to achieve. The method also includes moving, in response to receiving the initial data, an arm by an actuator to change a bend radius of an optical fiber wrap in the AAFOWP, thus adjusting an attenuation through the AAFOWP to the initial desired attenuation level.

Abstract: Example embodiments are in a form of a system, corresponding electronics card (or apparatus), or corresponding method. Some embodiments include a multi-channel optical layer system. According to some embodiments, the system may include a network interface layer, an adapter layer, and an optical function layer. The adapter layer may learn functions and/or corresponding specifications from the function layer. The adapter layer may configure the adapter layer itself to interoperate between the network interface layer and the optical function layer. The adapter layer may provide flexibility in the size of configured functionality. The adapter layer may reduce cost of configuration (or reconfiguration) because functions may be discretized. New markets may be reached because of this reduced cost, as well as due to smaller size configurations (of hardware and software), reduced electronics, reduced power, and improved thermal cooling requirements for lesser-developed network configurations.

Abstract: An optical transceiver system includes an optical transceiver chassis having a cable connector, a laser subsystem, and a laser shield system that is adjacent the cable connector. The laser shield system blocks a laser emitted by the laser subsystem when no cable is connected to the cable connector. In response to engagement with a transceiver connector on a cable, the laser shield system moves in order to allow the transceiver connector to connect to the cable connector.

Abstract: A device for optical communication is described. The device comprises two transceivers integrated on one chip. A first transceiver can be used with existing optical-communication architecture. As a more advanced optical-communication architecture becomes adopted, the device can be switched from using the first transceiver to using a second transceiver to communicate using the more advanced optical-communication architecture.

Abstract: Systems and methods for optically initiated information collection for network connected devices are provided. In one embodiment, a device comprises: at least one service port to connect a cable to the device; an optical information interface comprising: an optical information interface management function executed by a processor coupled to a memory; an optical information interface database that stores information associated with the device; and an optical emitter controller in communication with the optical information interface management function; wherein the optical information interface management function receives from the optical information interface database a set of information selected for optical broadcast; and wherein the optical emitter controller varies an optical output of at least one optical emitter to modulate the set of information selected for optical broadcast onto an optical signal generated by the at least one optical emitter.

Abstract: There is provided an OTDR receive device, an OTDR system comprising an OTDR receive device and an OTDR method wherein the OTDR unit and the OTDR receive device are to be connected at opposite ends of an optical fiber link under test. The OTDR receive device comprises means for the OTDR system to detect an established connectivity between the OTDR unit and the OTDR receive device via the optical fiber link under test and a status indicator to notify a user of the receive device of the connectivity status and optionally an OTDR measurement status. Connectivity detection allows to check for continuity between the OTDR unit and the OTDR receive device before launching an OTDR measurement. A user of the OTDR unit does not need to communicate with the user of the OTDR receive device to know when to start the acquisition.

Abstract: Quadrature amplitude modulation (QAM) techniques for use in optical systems are described. An optical transceiver may include a modulator configured to modulate data according to a scaled set-partitioning QAM (SP-QAM) scheme. The modulator may be configured to receive a plurality of bits, associate the plurality of bits with a plurality of symbols according to the scaled (SP-QAM) scheme; and transmit the plurality of symbols over an optical channel. A demodulator in an optical receiver may receive the plurality of symbols transmitted over the optical channel and associate the received symbols with a plurality of bits according to the scaled (SP-QAM) scheme; and provide the plurality of bits to a forward error correction decoder.

Abstract: A frame generating apparatus accommodating a client signal in an optical data transfer unit frame with a higher bit rate than the client signal includes a deserializer, a plurality of generic mapping procedure circuits, and a serializer. The deserializer deserializes the client signal into parallel signals, the number of parallel signals corresponding to the number of tributary slots used in the optical data transfer unit frame. The plurality of generic mapping procedure circuits inserts data and stuff into a frame accommodating portion of the optical data transfer unit frame based on a difference in the bit rate between the client signal and the optical data transfer unit frame. The serializer serializes the parallel signals output from the plurality of generic mapping procedure circuits.