162results about "Time-division optical multiplex systems" patented technology

The invention relates to the technical field of underground structure management, in particular to an underground structure full life cycle management method and system based on fusion sensing data. According to the technical scheme, the system comprises a sensing layer, a data transmission layer, a data processing and analysis layer and a decision support and application layer. Through cooperation of the distributed optical fiber sensor and the multiple sensors, all-around and multi-parameter monitoring of the underground structure is achieved, the monitoring accuracy and reliability are improved, historical data and operation rules of the structure are automatically learned through a data driving prediction model, different geological environments and load conditions are adapted, a scientific basis is provided for maintenance decision making, and meanwhile, the system has good application prospects. The self-adjusting capability is realized; monitoring system application and data accumulation and utilization in each stage are considered, seamless connection and cooperative work are achieved, full-life-cycle integrated management is achieved, the overall performance of the structure is improved, the service life of the structure is prolonged, the maintenance cost is reduced, and sustainable development is promoted.

The invention discloses a PON-based multi-protocol communication method and device, and the method comprises the steps: distributing a corresponding internal scheduling time slot to each network protocol processing unit for data uploading to each network protocol processing unit when a data processing module detects that the network protocol processing units connected with each field bus device have to-be-uploaded service data; and when one internal scheduling time slot is used up, interrupting the uploading of the service data until the next internal scheduling time slot allocated to the internal scheduling time slot is recovered from interrupting the uploading of the data. And the PON module monitors a global scheduling time slot allocation instruction issued by the optical line terminal in real time, converts an uploaded data frame into an electric signal, transmits the electric signal to the optical module through an internal link, converts the electric signal into an optical signal through the optical module in an allocated global scheduling time slot, and uploads the optical signal to the optical line terminal through an optical distribution network. Real-time performance and orderliness of transmission of service data in multiple field bus devices in a PON network are achieved, the requirement of industrial communication for data transmission is met, and transmission resource distribution is optimized.

A communication apparatus, a communication system, a communication method, and a non-transitory computer readable medium capable of reducing differences among receiving characteristics of a plurality of quadrature amplitude-modulated signals and optimizing the capacity of transmission signals are provided. A communication apparatus (1) according to the present disclosure includes a transmitting unit (2) capable of transmitting a plurality of types of quadrature amplitude-modulated signals, and an addition unit (3) that adds error correction codes to the quadrature amplitude-modulated signals. Further, the communication apparatus (1) includes a control unit (4) that changes the number of bits of the error correction code according to the type of the quadrature amplitude-modulated signal.

The invention discloses a ranging communication fusion miniaturized system and method based on single photon detection. The system adopts a time division multiplexing common-path structure, and a ranging pulse sequence and a communication pulse sequence are sequentially transmitted in the same detection period to form a PPM modulation laser pulse chain. A single-photon detector is adopted to receive signals, background light interference is suppressed by combining a narrow-band filter and a time gating technology, and the type and boundary of a pulse sequence are identified through a signal demodulation and discrimination module. When the distance measurement pulse sequence is identified, the distance measurement path realizes distance measurement based on the round-trip time of the distance measurement pulse in the period; when a communication pulse sequence is identified, the communication path demodulates the PPM communication data. The method effectively decouples the contradiction between the distance measurement fuzzy and the communication rate, supports communication pulse high repetition frequency modulation while realizing non-fuzzy distance measurement, improves the distance measurement precision and the communication rate, and is suitable for free space communication, mobile robot platforms and other application scenes.

An optical network communication system utilizes a CPON. The system includes an OLT and an ONU. The OLT includes an OLT transmitter for transmitting a downstream signal, and an OLT receiver for detecting an upstream signal. The downstream signal includes a first tone centered at a first frequency, a second tone centered at a second frequency, and first and second downstream subcarriers distributed proximate the first frequency. The upstream optical signal includes first and second upstream subcarriers distributed proximate the second frequency. The ONU includes an ONU receiver for detecting the first and second downstream subcarriers using the first optical tone to generate an LO signal for coherent detection, and an ONU transmitter configured to generate the first and second upstream subcarriers using the second optical tone. The first and second tones, downstream subcarriers, and upstream subcarriers do not overlap in the frequency domain

A method for monitoring an optical distribution network (ODN) in a passive optical network (PON), comprises establishing at least one data channel between an optical line terminal (OLT) and at least one optical network unit (ONU). The at least one ONU receives a live data traffic signal on at least one of the at least one data channel. The at least one ONU monitors the live data traffic signal for one or more abnormalities. The at least one ONU transmits an alert to the OLT when one or more abnormalities is detected.

An embodiment mixes classical and quantum signals in the same transmission such that an eavesdropper can be detected using the quantum signals while maintaining high classical transmission rates. The embodiment uses security enhancement from quantum signals while maintaining the high data rates of classical communication. The eavesdropper introduces noise when trying to collect information on the physical layer. This noise can be observed by monitoring the quantum signals.

A communication system includes an aggregate station configured to transmit and receive a signal and N extension stations (N is an integer of 2 or more). The N extension stations include a first extension station configured to receive a signal from the aggregate station and transmit a signal to a second extension station, an ith extension station (i is an integer satisfying 2 ≤ i ≤ N-1) configured to receive a signal from an (i-1)th extension station and transmit a signal to an (i+1)th extension station, and an Nth extension station configured to receive a signal from an (N-1)th extension station. A ratio between a magnitude of a signal to be received by an ith extension station (1 ≤ i ≤ N-1) and a magnitude of a signal to be transmitted thereby is (N-i+1):(N-i).

An optical communication device includes a signal multiplexing unit that multiplexes a plurality of client signals and a signal transmission unit that converts a first multiplexed signal obtained by the multiplexing to an optical signal and transmits the optical signal. The optical communication device is a device capable of receiving data traffic greater than data traffic corresponding to a predetermined communication bandwidth.

Provided herein is a probe for treating an eye of a patient. In one or more embodiments, the probe includes a body, and a tubular element having a main lumen extending from the body, the tubular element comprising a distal end. The probe further includes a visualization optical fiber within the main lumen, the visualization optical fiber adapted to emit an illumination provided by at least one of a plurality of light sources connected to the visualization optical fiber. In some embodiments, the probe further includes an optical switching system (e.g., a time-division multiplexor) operable with the plurality of light sources, wherein the optical switching system is adapted to independently control each of the plurality of light sources. By providing time-division multiplexing between different surgical light sources, quasi-simultaneous illumination delivery through the same optical path may be achieved.

Embodiments of this application provide a service data processing method. The method includes: receiving service data, performing encapsulation, rate matching, and timeslot multiplexing on the service data by code block to obtain an intermediate frame, mapping the intermediate frame to an OTN frame, and sending the OTN frame. A size of the code block is a plurality of bytes, and the code block includes information indicating a code block type. If the code block is an overhead code block or a rate adaptation code block, the code block further includes information indicating a timeslot multiplexing layer at which the code block is located. In all processing procedures of the service data, the service data is processed at a uniform code block processing granularity, and this reduces complexity of the service data processing.

Provided is a data synchronization method for a passive optical network. The method comprises: an alignment and restoration step of synchronously aligning a plurality of first data signals, and restoring the aligned plurality of first data signals into a second data signal; performing passive optical network synchronization verification on the second data signal; if the second data signal fails to pass the passive optical network synchronization verification, turning to the alignment and restoration step; and if the second data signal passes the passive optical network synchronization verification, determining that synchronization is successful.

A network or system in which a hub or primary node may communicate with multiple leaf or secondary nodes. The hub node may operate at or have a capacity greater than that of the leaf nodes. Accordingly, relatively inexpensive leaf nodes may be deployed that receive data carrying optical signals from the hub node and provide data carrying optical signals to the hub node. One or more connections may couple each leaf node to the hub node, whereby each connection may include, for example, one or more spans or segments of optical fiber, optical amplifiers, optical splitters / combiners, and optical add / drop multiplexers. Optical subcarriers may be transmitted across such connections, each carrying a data stream. The subcarriers may be generated by a combination of lasers and modulators, eliminating the need for and reducing costs of multiple lasers and modulators. Furthermore, as the bandwidth or capacity requirements of the leaf nodes change, the number of subcarriers, and therefore the amount of data provided to each node, may change accordingly. Each subcarrier within a dedicated group of subcarriers may carry OAM or control information to a corresponding leaf node, and such information may be used by the leaf node to configure the leaf node to have a desired bandwidth or capacity.

A coherent transmitter (100, 200) for use in a time division multiple access (TDMA) system is operated in multiple states to enable coherent burst transmission. In an OFF state, the transmitter (100, 200) generates a dummy laser output (fd) from either a dummy laser (102) or an active laser (52) tuned to a dummy frequency different from an active frequency (fa), thereby maintaining thermal and bias stability without adding excess power on an upstream channel (22). In an ON state, the active laser (52) produces an active laser output (fa) that is modulated by a quad-parallel Mach-Zehnder (QPMZ) modulator (60) to transmit data. A thermoelectric cooler (TEC) (58) stabilizes laser temperatures, and a variable optical attenuator (VOA) (54) controls output power. The transmitter (100, 200) is suitable for an optical network unit (ONU) (14) in a passive optical network (PON) (10) communicating with an optical line terminal (OLT) (12).

A spatiotemporal optical multiplexer includes a storage optical cavity having a plurality of storage-cavity modes that are transversely separated, a dump optical cavity having a plurality of dump-cavity modes that are transversely separated, and a phase modulator located in the dump cavity and overlapping all of the dump-cavity modes. Each dump-cavity mode is coupled to a respective storage-cavity mode. The storage-cavity modes have the same storage-cavity resonant frequency while the dump-cavity modes have dump-cavity resonant frequencies that are distinct. The phase modulator is driven to simultaneously tune the dump-cavity resonant frequencies. At any time, no more than one dump-cavity mode is resonant with its respective storage-cavity mode. When this resonance occurs, the energy of the respective storage-cavity mode is coupled out of the storage cavity and through the dump cavity as an output pulse.

A generator device for generating an arbitrary optical pulse pattern includes:a light source to provide primary laser pulses,a distributor to provide a plurality of primary optical pulses by distributing light of the primary laser pulses (LB00k) into a plurality of branches,a combiner to form an output signal by combining modulated optical signals from the branches, anda controller unit to provide control signals for controlling optical modulators of the branches,wherein a first branch comprises a first optical modulator to form a first modulated optical signal from primary optical pulses of the first branch,wherein a second branch comprises a second optical modulator to form a second modulated optical signal from primary optical pulses of the second branch, andwherein a propagation delay of the second branch is different from a propagation delay of the first branch.

Embodiments of the present disclosure relate to the field of optical communications technologies, and in particular, to a mapping and multiplexing method and apparatus for an optical transport network, an electronic device, and a storage medium. The mapping and multiplexing method for the optical transport network includes: first providing a mapping opportunity generated by an Optical Channel Payload Unit (OPU) in a current transport window to one or more Optical Service Unit (OSU) services, which satisfy a first scheduling condition, in a first queue, and performing in-queue scheduling on the one or more OSU services, which satisfy the first scheduling condition, in the first queue; in a case where there is no OSU service satisfying the first scheduling condition in the first queue, providing the mapping opportunity to one or more OSU services, which satisfy a second scheduling condition, in a second queue, and performing in-queue scheduling on the one or more OSU services, which satisfy the second scheduling condition, in the second queue; updating a remaining service mapping opportunity quantity of the OSU service which gets the mapping opportunity, wherein a service mapping opportunity quantity of respective OSU service in one transport window is independently set; and dynamically allocating OSU services entering mapping and multiplexing in the current transport window to the first queue and the second queue according to the remaining service mapping opportunity quantity of respective OSU service.

A network or system in which a hub or primary node may communicate with a plurality of leaf or secondary nodes. The hub node may operate or have a capacity greater than that of the leaf nodes. Accordingly, relatively inexpensive leaf nodes may be deployed to receive data carrying optical signals from, and supply data carrying optical signals to, the hub node. One or more connections may couple each leaf node to the hub node, whereby each connection may include one or more spans or segments of optical fibers, optical amplifiers, optical splitters / combiners, and optical add / drop multiplexer, for example. Optical subcarriers may be transmitted over such connections, each carrying a data stream. The subcarriers may be generated by a combination of a laser and a modulator, such that multiple lasers and modulators are not required, and costs may be reduced. As the bandwidth or capacity requirements of the leaf nodes change, the number of subcarriers, and thus the amount of data provided to each node, may be changed accordingly. Each subcarrier within a dedicated group of subcarriers may carry OAM or control channel information to a corresponding leaf node, and such information may be used by the leaf node to configure the leaf node to have a desired bandwidth or capacity.

This application provides a data transmission method and apparatus. The method includes: processing, by a network device, a to-be-sent optical data unit ODD to obtain another ODU, where a bit rate of the another ODU is lower than a bit rate of the ODU; and sending, by the network device, the another ODU. In embodiments of this application, the ODU is processed to obtain the another ODU with a lower bit rate, and this helps reduce a rate increase when service data is transmitted in an OTN, so as to reduce an OTN interface rate and OTN costs.

This optical communication system (40) comprises: a control unit (10) that controls the transmission timings of packet signals transmitted from optical transmitters (1-1 to 1-M) and calculates a scheduled reception time for each redundant packet signal for each of optical receivers (2-1 to 2-M+1); a transmission information holding unit (8) that provides reception data information indicating a packet signal scheduled to be received; a selection control management unit (9) that outputs, on the basis of the reception data information, memory destination information indicating a memory in which the packet signal indicated by the reception data information is stored and output destination information indicating an output destination of the packet signal indicated by the reception data information, from among memories (5-1 to 5-M+1) in which the packet signals received by the optical receiver (2-1 to 2-M+1) are stored; and a packet selection unit (6-1) that selects two memories of reference destinations from the memories (5-1 to 5-M+1) on the basis of the memory destination information, acquires a packet signal from one memory, and outputs the packet signal to an output destination indicated by the output destination information.

An optical communication device, system, and communication method are disclosed. The optical communication device is used to communicate with multiple ONUs, including first-type ONUs and second-type ONUs. The first-type ONUs and second-type ONUs support different MAC protocols, and their uplink wavelengths overlap. The optical communication device includes: a first receiving component, a second receiving component, and a processing component. The first receiving component is used to receive a first optical signal transmitted by a first-type ONU in a first time slot group, and the second receiving component is used to receive a second optical signal transmitted by a second-type ONU in a second time slot group. The first time slot group includes at least one time slot, and the second time slot group includes at least one time slot. The processing component is used to ensure that the first and second time slot groups do not overlap in the time dimension through a first time slot scheduling mechanism. This enables the coexistence of ONUs supporting different MAC protocols and with overlapping uplink wavelengths in a PON system.

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.

A network adapter includes a host interface and a scheduler. The host interface is configured to receive, from one or more hosts, packets for transmission to respective destinations over a network. The scheduler is configured to synchronize to a time-division schedule that is employed in the network, the time-division schedule specifying (i) multiple e time-slots and (ii) multiple respective groups of the destinations that are reachable during the time-slots, and, based on the time-division schedule, to schedule transmission times of the packets to the network on time-slots during which the respective destinations of the packets are reachable.

Provided is a data synchronization method for a passive optical network. The method comprises: an alignment and restoration step of synchronously aligning a plurality of first data signals, and restoring the aligned plurality of first data signals into a second data signal; performing passive optical network synchronization verification on the second data signal; if the second data signal fails to pass the passive optical network synchronization verification, turning to the alignment and restoration step; and if the second data signal passes the passive optical network synchronization verification, determining that synchronization is successful.

To realize a high speed of an optical transmitter transmitting a multilevel optical signal.SOLUTION: An optical transmitter comprises: a signal generation circuit; a Mach-zehnder interferometer; and an M*N movement phase segments, and transmits a modulation optical signal for transmitting an M bit by each symbol. The signal generation circuit generates M*N binary electric signals each having the same bit rate from transmission data when the optical transmitter multiples N optical signals by a time division multiplexing. The M*N movement phase segments are provided along an optical path of the Mach-zehnder interferometer, and makes an optical phase transmitting each optical path in accordance with the M*N binary electric signals shift. The M*N movement phase segments are constructed by N electrode groups. Each electrode group contains M or more electrodes to which the M binary electric signals corresponded to them from the M*N binary electric signals are applied.SELECTED DRAWING: Figure 10

Methods and systems for reducing power consumption in a multi-channel passive optical network (PON). A processor in the PON may monitor the channels in the multi-channel PON to detect a currently inactive channel, determine whether the detected channel has been inactive for an extended period of time, and deactivate the detected channel (by deenergizing transmitter(s) and / or receiver(s) associated with the detected channel) in response to determining that the channel has remained inactive for an extended period of time. The processor may re-activate the channel in response to determining that an optical signal has been reliably present on the channel for a sufficient period of time.

This application discloses a communication method. The method includes: A first apparatus generates and sends a first optical signal, where the first optical signal is a signal obtained by combining a first clock signal with a downlink digital signal, and the first clock signal includes a first transmission delay; and a second clock signal is obtained by transmitting the first clock signal on a transmission link, a sum of a transmission delay of the transmission link and the first transmission delay is zero. A second apparatus performs time synchronization based on the second clock signal. In technical solutions of this application, digital-analog hybrid transmission and simultaneous transmission of the clock signal and the downlink digital signal may be completed through one transmission link, and an independent clock signal transmission link does not need to be established. In addition, after transmission of the first clock signal on the transmission link, the first transmission delay in the first clock signal may be canceled by the transmission delay of the transmission link, and the transmission delay of the transmission link does not need to be measured or calculated, thereby improving accuracy of time synchronization.

A system includes an optical transmitter configured to modulate a pulsed laser signal based on a plurality of data signals to form a plurality of modulated optical data signals, perform optical time division multiplexing of the plurality of modulated optical data signals to obtain a multiplexed optical data signal, and transmitting the multiplexed optical data signal together with an optical clock signal derived from the pulsed laser signal; and an optical receiver comprising a clock recovery branch configured to recover the optical clock signal to a plurality of phase shift recovered optical clock signals and a data branch having a plurality of saturable absorbers (SAs), each SA being in optical communication with one of the phase shift recovered optical clock signals, and configured to receive the multiplexed optical data signal and to transmit one of the plurality of modulated optical data signals according to the recovered optical clock signal.