Patent application number | Description | Published |
20080317469 | PASSIVE OPTICAL NETWORK SYSTEM AND RANGING SYSTEM THEREOF - A station-side communication device connected to subscriber-side communication devices via an optical combining device; sending, to the subscriber-side communication devices, a distance measurement request signal; computing transmission delay times of optical signals from the individual subscriber-side communication devices by receiving distance measurement signals, and including: a threshold control part identifying the level of distance measurement signals; a signal detection part detecting breaks in the distance measurement signals from the threshold control part; a transmission granting part determining the timing at which transmission of optical signals is granted, and a reset timing generation part that, there is notification of detection of a break in the distance measurement signal from the signal detection part while it is being notified that distance measurement is carried out to and from the subscriber-side communication devices from the transmission granting part, sends a reset signal indicating that the voltage level is reset to the threshold control part. | 12-25-2008 |
20090010650 | PASSIVE OPTICAL NETWORK SYSTEM AND COMMUNICATION METHOD THEREFOR - In a passive optical network system in which communication signals from a master station to a plurality of subsidiary stations are multiplexed by time division and transmitted, after converting (modulating) data with a high transmission speed to a low transmission speed, a base speed, in the master station, a header including an identifier destined for each subsidiary station is attached to the data with a low transmission speed and the converted data, respectively, the data and the header being multiplexed by time division inside a frame and transmitted to the subsidiary stations at the base speed. In the subsidiary station having received the concerned frame, only the data destined for the station itself is read, on the basis of the identifier included in the header, and by means of demodulation, the converted data are reconverted to the original high speed data and supplied to a user terminal. | 01-08-2009 |
20090034973 | PASSIVE OPTICAL NETWORK SYSTEM AND OPTICAL LINE TERMINAL - In order to be able to moderate the inclination of the PON burst reception characteristics and to improve the FEC effect, a first offset is used in a ranging window field, and a second offset, which is lower than the first offset value, is used in a burst data field other than the ranging window field. | 02-05-2009 |
20090052896 | PASSIVE OPTICAL NETWORK SYSTEM AND RANGING SYSTEM THEREOF - A station-side communication device connected to subscriber-side communication devices via an optical combining device; sending, to the subscriber-side communication devices, a distance measurement request signal; computing transmission delay times of optical signals from the individual subscriber-side communication devices by receiving distance measurement signals, and including: a threshold control part identifying the level of distance measurement signals; a signal detection part detecting breaks in the distance measurement signals from the threshold control part; a transmission granting part determining the timing at which transmission of optical signals is granted, and a reset timing generation part that, there is notification of detection of a break in the distance measurement signal from the signal detection part while it is being notified that distance measurement is carried out to and from the subscriber-side communication devices from the transmission granting part, sends a reset signal indicating that the voltage level is reset to the threshold control part. | 02-26-2009 |
20090052897 | PASSIVE OPTICAL NETWORK SYSTEM AND RANGING SYSTEM THEREOF - A station-side communication device connected to subscriber-side communication devices via an optical combining device; sending, to the subscriber-side communication devices, a distance measurement request signal; computing transmission delay times of optical signals from the individual subscriber-side communication devices by receiving distance measurement signals, and including: a threshold control part identifying the level of distance measurement signals; a signal detection part detecting breaks in the distance measurement signals from the threshold control part; a transmission granting part determining the timing at which transmission of optical signals is granted, and a reset timing generation part that, there is notification of detection of a break in the distance measurement signal from the signal detection part while it is being notified that distance measurement is carried out to and from the subscriber-side communication devices from the transmission granting part, sends a reset signal indicating that the voltage level is reset to the threshold control part. | 02-26-2009 |
20090080891 | PASSIVE OPTICAL NETWORK SYSTEM AND RANGING METHOD - In a WDM-PON system wherein a plurality of ONUs transfer signals by sharing wavelengths, one wavelength dedicated to a ranging procedure is set, and the ranging is performed with only the dedicated wavelength, so as to measure reciprocating delay times. At the other wavelengths, transmission signals from a plurality of ONUs are transferred in time division multiplexing based on the obtained reciprocating delay times. An OLT includes a burst receiver circuit for only the wavelength dedicated to the ranging, and subsequently to the ranging, the OLT adjusts transmission amplitudes and transmission phases for the ONUs, so as to equalize received amplitudes and received phases in the OLT. For this purpose, the OLT includes means for measuring the amplitudes and phases of received signals, as the burst receiver circuit, and it includes a table for managing the received amplitudes and received phases of the respective ONUs. | 03-26-2009 |
20090123160 | BIT SYNCHRONIZATION CIRCUIT WITH PHASE TRACKING FUNCTION - A bit synchronization circuit comprising an initial phase determining unit for rapidly determining, during a period of receiving a preamble of burst data, a clock with a phase synchronized with received burst data from among multi-phase clocks having the same frequency as an internal reference clock and a phase tracking unit for modifying the synchronized phase clock responsive to phase variation of received data during a period of receiving a payload of burst data by taking the synchronized phase clock determined by the initial phase determining unit as an initial phase. The bit synchronization circuit retimes burst data with a data retiming clock having a predetermined phase relation with the synchronized phase clock and outputs the burst data in synchronization with the internal reference clock. | 05-14-2009 |
20090162053 | PON system method for receiving optical signal and OLT - When a signal of weak optical power is received immediately after a signal of intense optical power, input of the signal of intense optical power readily causes saturation, and the influence interferes in the signal of weak optical power to deteriorate receiver sensitivity. Moreover, when a reverse-bias voltage of APD is changed, if a difference between the voltages is large, a next optical signal is received until the receiver sensitivity of the APD becomes stable, so that receiver sensitivity deteriorates. A DBA order is determined so that a difference in reverse-bias voltage is small, and reverse-bias voltage is controlled in line with reception timing from ONU. | 06-25-2009 |
20090169209 | Network system, optical line terminating apparatus, and optical network apparatus - A general object of the present invention is to provide an optical communication system in which an optical transmission power of an optical communication apparatus is controlled to be a required minimum power that apparatuses of all subscribers in the optical communication system meet a prescribed error rate. An optical line terminating apparatus (OLT) transmits data to multiple optical network apparatuses (ONUs) at an optical intensity calculated based on information acquired from the multiple ONUs, which is related to optical intensities of signals that the multiple ONUs receive from the OLT, the optical intensity being calculated so that a minimum optical intensity of the optical intensities of the signals is greater than a predetermined value. | 07-02-2009 |
20090202242 | PASSIVE OPTICAL NETWORK SYSTEM, OPTICAL LINE TERMINATOR AND, COMMUNICATION METHOD OF PASSIVE OPTICAL NETWORK SYSTEM - A passive optical network system (PON) has a plurality of OLTs and ONUs with different transmission rates. OLTs with different transmission rates share information of priority frames and destinations, and determine timing for frame transmission to ONUs so that the signal from each of the OLTs does not collide when multiplied in a splitter. OLTs transmit the data to the ONU as a burst signal to prevent the signals with different rates from colliding. ONU acquires the information of the following burst frames. ONU receives only the signal addressed to the own ONU or with the transmission rate of own ONU, therefore errors in ONUs can be avoided. OLT receives only the signal with the transmission rate of own OLT from ONUs based on the transmission timing from the ONUs shared by the line terminators, errors in OLTs can be avoided. | 08-13-2009 |
20090214211 | APPARATUS OF ADJUSTING OPTICAL SIGNAL TRANSMISSION TIMING - In a light reception element such as an APD (Avalanche Photo Diode) used for receiving a high-speed and weak optical signal, it is possible to prevent the phenomenon of distortion of a signal inputted after a large-level light is received. A PON (Passive Optical Network) system includes an OLT (Optical Line Terminal) which can impartially and effectively transmit light reception data to each ONU (Optical Network Unit). According to a light reception amplitude received by each ONU, an inter-frame gap of an appropriate length is assigned for each ONU. The OLT includes a unit for measuring and accumulating the reception light amplitude and data on the inter-frame gap of an appropriate length decided in advance according to the characteristic of the light reception device and generates a grant value for assuring an inter-frame gap of an appropriate length by using the both information. | 08-27-2009 |
20090245790 | PASSIVE OPTICAL NETWORK SYSTEM AND OPERATION METHOD OF THE SAME - In a passive optical network system, in order that by measuring a transmission distance and a transmission time between an OLT and an ONU in operation of the system, if the distance or the time is short, communication is conducted at a high transmission speed to increase a capacity of user; if the distance or the time is long, communication is conducted at a low transmission speed to increase the capacity of user communicating in a state in which a predetermined quality is secured, a main station includes a signal communication circuit to communicate with subsidiary stations at a first or second transmission speed and a controller to measure a transmission distance or a transmission time between the main station and each subsidiary station. Based on a result of the measurement, the controller selects a transmission speed for communication with the subsidiary station. | 10-01-2009 |
20090304388 | Optical Branching Apparatus and Passive Optical Network System - In the case where, in a WDM-PON system, a high-output optical signal or a pseudo signal for illegal access by a hostile user, or an optical signal with a wavelength which is not assigned from an OLT is input to an ONU-side optical fiber, the quality of communications for other users is possibly affected and a receiver on the station side is possibly destroyed. By providing an optical blocking unit at a position near an ONU-side optical splitter of an optical branching unit, in the case where input of an extraordinary optical signal is detected, an optical route into which the extraordinary optical signal is input is blocked, so that the input of the extraordinary optical signal to an OLT and optical lines shared by plural users can be preliminarily blocked. | 12-10-2009 |
20090310964 | Optical communication system and optical line terminating apparatus - There is provided an abnormal light cut-off system in which even when a high power light is inputted from an optical fiber connected to a user side apparatus by a malicious user or an accident, a trouble rate is low, the abnormal light is cut off at high sensitivity, and security is high. In a network system in which an optical line terminating apparatus and plural optical network apparatuses are connected together via plural optical connection sections and an optical branching section, the optical branching section includes one optical line terminating apparatus side port and plural optical network apparatus side branch ports, an optical line terminating apparatus side optical fiber connects the optical line terminating apparatus and the one optical line terminating apparatus side port, an optical branching section side optical fiber connects the optical network apparatus side branch port and a light cut-off section, and an optical network apparatus side optical fiber connects the light cut-off section and the optical network apparatus. When an abnormal light is inputted from the optical network apparatus side, it is cut off by the light cut-off section. | 12-17-2009 |
20090317082 | Passive Optical Network System, Optical Network Unit, and Optical Line Terminal - An optical line terminal (OLT), an optical network unit (ONT) and a passive optical network (PON) system are provided. A user of the ONU or a terminal connected with the ONU can accurately recognize the amount of a bandwidth allocated to the ONU without estimating the communication bandwidth. The OLT notifies each ONU of the amount of the bandwidth allocated to the ONU in response to a request transmitted from the ONU to the OLT. Each ONU receives bandwidth information from the OLT and displays thereon the bandwidth information or notifies the terminal connected with the ONU of the bandwidth information. | 12-24-2009 |
20100002591 | Communication System and Communication Apparatus - Communication time period measuring frames are simultaneously sent from an OAM adaptive device on a transmission side, to both a working path and a protection path. In an OAM adaptive device on a reception side, reception times of the frames having arrived from both the paths are checked so as to measure a time period difference between both the paths. The time period difference is fed back to a logic distance adjustment function of each PON section to determine required communication time periods of the PON sections respectively included in a working system and a protection system. Communication time periods of the working system and the protection system in a packet communication network are arbitrated in order to decrease a packet loss at line switching in a packet relaying network. | 01-07-2010 |
20100067901 | Passive optical network system and fault determination method - In a passive optical network system, a parent station includes a reception circuit that receives an optical signal from each of child stations using a threshold used to identify if the optical signal is 0 or 1; a bandwidth setting unit that determines a time at which each child station sends an optical signal; a storage unit that stores thresholds and intensities of optical signals received from the child stations; and a control unit that sets a threshold, stored corresponding to a sending time, in,the reception circuit to control a reception of an optical signal. The control unit has a function that compares an intensity of a signal received from each child station at an optical signal reception time with information stored in the storage unit to detect and determine a fault in the child station or in the optical fiber connected to the child station. | 03-18-2010 |
20100080558 | Passive Optical Network System and Operating Method Thereof - The passive optical network includes a master station and slave stations connected via an optical fiber network including an optical splitter and a plurality of optical fibers. The master station includes a bandwidth control unit which decides a volume of a transmission signal to be granted to each slave station in every first period and in accordance with a request from the slave station, and a transmission timing control unit which decides, in one of a plurality of second periods and in accordance with the decided volume of the signal, transmission timing in which the slave station should transmit a signal. When the signal is to be transmitted by division over the plurality of second periods, the bandwidth control unit or the transmission timing control unit is controlled based on a volume of a signal to be attached by division processing, so that the granted signal can be transmitted in the first period. | 04-01-2010 |
20100178051 | OPTICAL COMMUNICATION SYSTEM AND METHOD FOR OPERATING THE SAME - An optical communication system has a master station and a plurality of slave stations connected thereto via an optical fiber network, which is provided with an optical splitter and a relay unit which relays signals transmitted/received between the master station and the plurality of slave stations. The master station includes a first controller for performing ranging between the master station and the relay unit, and the relay unit includes a second controller for performing ranging between the relay unit and the plurality of slave stations. The master station determines, on the basis of the results of ranging performed by the first and second controllers as well as reports from the slave stations, timings for the slave stations to transmit signals to the master station, and receives signals multiplexed through the optical fiber network from the slave stations. | 07-15-2010 |
20100272436 | OPTICAL PASSIVE NETWORK SYSTEM AND ITS OPERATION METHOD - In the configuration of an optical communication system interconnecting a parent station and a plurality of child stations via an optical fiber network equipped with an optical splitter, RE is provided having a measuring unit for measuring a transmission distance or time to a child station, a determining unit for determining a timing when a child station transmits a signal, in accordance with a transmission bandwidth request from the child station, and a signal processing unit for processing a signal received from a child station and transmitting the processed signal to the parent station. When a burst signal is received from each child station at the determined timing, a portion of the header of the burst signal is deleted, and a dummy signal is inserted into the deleted area and a gap area between received burst signals to convert the burst signals into a series of signals to be sent to the parent station. | 10-28-2010 |
20100296811 | OPTICAL ACCESS SYSTEM - There are provided multiple candidates for FEC codes selectable for each of the ONTs. An OLT is provided with: means for storing redundancy and a code length of each FEC code in a table; means for selecting an FEC code; means for encoding or decoding data using the selected FEC code; means for calculating a bandwidth in consideration for the FEC redundancy and the code length with reference to the table during band assignment calculation; and means for notifying the destination ONT of the selected FEC code. | 11-25-2010 |
20110170871 | APPARATUS OF ADJUSTING OPTICAL SIGNAL TRANSMISSION TIMING - In a light reception element such as an APD (Avalanche Photo Diode) used for receiving a high-speed and weak optical signal, it is possible to prevent the phenomenon of distortion of a signal inputted after a large-level light is received. A PON (Passive Optical Network) system includes an OLT (Optical Line Terminal) which can impartially and effectively transmit light reception data to each ONU (Optical Network Unit). According to a light reception amplitude received by each ONU, an inter-frame gap of an appropriate length is assigned for each ONU. The OLT includes a unit for measuring and accumulating the reception light amplitude and data on the inter-frame gap of an appropriate length decided in advance according to the characteristic of the light reception device and generates a grant value for assuring an inter-frame gap of an appropriate length by using the both information. | 07-14-2011 |
20110200326 | PASSIVE OPTICAL NETWORK SYSTEM AND RANGING METHOD - In a WDM-PON system wherein a plurality of ONUs transfer signals by sharing wavelengths, one wavelength dedicated to a ranging procedure is set, and the ranging is performed with only the dedicated wavelength, so as to measure reciprocating delay times. At the other wavelengths, transmission signals from a plurality of ONUs are transferred in time division multiplexing based on the obtained reciprocating delay times. An OLT includes a burst receiver circuit for only the wavelength dedicated to the ranging, and subsequently to the ranging, the OLT adjusts transmission amplitudes and transmission phases for the ONUs, so as to equalize received amplitudes and received phases in the OLT. For this purpose, the OLT includes means for measuring the amplitudes and phases of received signals, as the burst receiver circuit, and it includes a table for managing the received amplitudes and received phases of the respective ONUs. | 08-18-2011 |
20110268435 | COMMUNICATION SYSTEM, SUBSCRIBER ACCOMMODATING APPARATUS AND COMMUNICATION METHOD - Switching process at the occurrence of a path trouble is performed more quickly to reduce the number of packet discards during a traffic transition from a currently used system path to a standby system path within a section to be protected. An OLT ( | 11-03-2011 |
20110293274 | PASSIVE OPTICAL NETWORK SYSTEM AND OPTICAL LINE TERMINAL - In order to be able to moderate the inclination of the PON burst reception characteristics and to improve the FEC effect, a first offset is used in a ranging window field, and a second offset, which is lower than the first offset value, is used in a burst data field other than the ranging window field. | 12-01-2011 |
20120008948 | PASSIVE OPTICAL NETWORK SYSTEM AND OPERATING METHOD THEREOF - Provided is a passive optical network system for operating a mixture of PONs with differing transmission speeds and is capable of reducing power consumption on the basis of the amount of signals being transmitted. The master station of the passive optical network system, which determines the amount and timing of signals sent thereto by each of a plurality of slave stations on the basis of the requests of the plurality of slave stations and receives signals from the plurality of slave stations via an optical fiber network, is equipped with a control unit that determines in each set cycle the amount, transmission timing, and transmission speed of the signals that each slave station is permitted to transmit to said master station on the basis of the amount of signals that each of the plurality of slave stations has requested to transmit, and that notifies such to each slave station. Additionally, each of the plurality of slave stations is equipped with a control unit that transmits signals to the master station at a first transmission speed or a second transmission speed that is faster than the first transmission speed, and is configured to transmit signals with either the first transmission speed or the second transmission speed on the basis of notifications from the master station. | 01-12-2012 |
20120070147 | COMMUNICATION SYSTEM AND COMMUNICATION APPARATUS - Communication arrangements wherein each of ONUs of a first or second PON transmits data toward a connected first or second OLT after a wait time period designated by the connected first or second OLT; the first communication device of the first packet communication network sends a first frame for measuring communication time period, to the second communication device of the second packet communication network through the first PON, and sends a second frame for measuring communication time period, to the second communication device through the second PON; and the second communication device calculates a difference of communication time period between the received first and second frames, and instructs the first or second OLT of the first or second PON, for correcting a wait time period which is set to the one or plural ONUs connected to the first or second OLT, based on the difference between communication time periods. | 03-22-2012 |
20130322450 | COMMUNICATION APPARATUS AND COMMUNICATION METHOD - In an exemplary communication apparatus, an assignment module determines whether processing for a second packet assigned the flow ID associated with a received first packet is being executed. The assignment module determines a parallel processing module to execute processing for the first packet and a parameter to be included in a notice of assignment. The determined parallel processing module acquires a result of execution of the processing for the second packet from the computation table or the result of execution of the processing held in the parallel processing module according to the received notice of assignment. The determined parallel processing module executes the processing for the first packet using the result of execution of the processing for the second packet and the information included in the notice of assignment, and updates a computation table with a result of execution of the processing for the first packet. | 12-05-2013 |
20140010233 | COMMUNICATION DEVICE, METHOD FOR CONTROLLING THE COMMUNICATION DEVICE, AND COMMUNICATION SYSTEM - A communication device includes a flow identification unit specifying a user corresponding to received data, a bandwidth control unit controlling transmission of the received data so as not to exceed a bandwidth corresponding to the selected communication path in two bandwidths allocated to the specified user, and a label addition unit adding the label value corresponding to the selected communication path to the data received from the bandwidth control unit and transmitting the data. The label addition unit executes, upon detecting a trigger for a change in the selection of the communication path, changing the selection of the label value and transmitting a feedback signal for giving notice of the change in the selection of the communication path to the bandwidth control unit in a given order. The bandwidth control unit executes a process of changing the setup of the bandwidth on the basis of the received feedback signal. | 01-09-2014 |