| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 398037000 | Amplifier or repeater operation | 22 |
| 20080253764 | Methods and systems to stabilize an optical network against nodal gain changes - The present invention provides methods and systems to stabilize an optical network against nodal gain changes through two nested control loops for controlling node gain and node output power. The present invention includes two nested control-loops running at different update speeds including: an inner, faster, control-loop which sets the gains and losses within a node to achieve a node-gain target, and a node-gain target for the inner loop is set by an outer, slower, control loop that whose target is the node output power. Advantageously, the present invention reduces the problem of concatenated overshoot by minimizing the control-loop response to events that occur at other nodes. | 10-16-2008 |
| 20090269058 | System and Method for Self-Generation of Reference Signals - One embodiment of the present invention sets forth a technique for determining properties of optical links using the amplified spontaneous emission (ASE) of integrated amplifiers. To calibrate the system, existing amplifiers in the nodes of the system can be operated in an ASE mode. A bypass switch at the mid-stage of each amplifier routes the ASE from the amplifier's first stage into one or more signal processing components, creating reference signals. Subsequently, the bypass switch routes the reference signals back into the mid-stage of the amplifier. After propagating through a link to the next node in the system, the optical parameters of the reference signals are measured and used to determine properties of the link, such as chromatic dispersion and attenuation. Tunable devices within the two nodes connected by the link may be set to compensate for specific properties of the link, thereby improving the quality of transmitted signals. | 10-29-2009 |
| 20090279888 | Alien wavelength channel balancing and line amplifier optimization - An algorithm is disclosed for performing alien-wavelength channel balancing on channels between optical network elements within an optic-fiber communications system. The algorithm determines initial values of various optimization parameters for each of the channels, such as the input launch power and operating conditions of optical amplifiers in the optical path, and calculates an initial total optimization offset for the channels based on the initial values of the optimization parameters for each of the channels. The algorithm then adjusts the optimization parameters to new values and calculates a new total optimization offset based on the new optimization parameter values. The algorithm repeats this process until the relative channel launch powers and optical amplifiers are optimized. | 11-12-2009 |
| 20110069952 | Circuit for End-of-Burst Detection - A circuit for end-of-burst detection in a portion of a received bit stream is disclosed. The circuit comprises:
| 03-24-2011 |
| 20110085799 | OPTICAL COMMUNICATION SYSTEM AND COMMUNICATION BANDWIDTH CONTROL METHOD - In the communication system, a master station is coupled to slave stations by a fiber network comprising a splitter and a reach extender, the master station includes a first bandwidth control section which determines, based on a request from each slave station, a first data amount of a signal transmitted in a first cycle, the reach extender includes: a distance measurement section which measures a distance or a time between the reach extender and each slave station; and a second bandwidth control section which determines a second data amount and transmission timing of a signal based on a request from each slave station and the first data amount, and each slave station transmits a signal with a data amount, which the first bandwidth control section determined based on a data amount and transmission timing determined in second cycles, to the master station in the first cycle. | 04-14-2011 |
| 20110103793 | METHODS AND SYSTEMS TO STABILIZE AN OPTICAL NETWORK AGAINST NODAL GAIN CHANGES - The present invention provides methods and systems to stabilize an optical network against nodal gain changes through two nested control loops for controlling node gain and node output power. The present invention includes two nested control-loops running at different update speeds including: an inner, faster, control-loop which sets the gains and losses within a node to achieve a node-gain target, and a node-gain target for the inner loop is set by an outer, slower, control loop that whose target is the node output power. Advantageously, the present invention reduces the problem of concatenated overshoot by minimizing the control-loop response to events that occur at other nodes. | 05-05-2011 |
| 20110293269 | RELAY STATION ARRANGEMENT METHOD AND RELAY STATION ARRANGEMENT DEVICE - A method for arranging relay stations in an optical transmission system including relay stations arranged so that optical signals at a first transmission speed can be transmitted from a transmission end to a reception end, includes: judging whether a transmission of optical signals at a second transmission speed different from the first transmission speed in a section connecting arbitrary two of the relay stations where a regenerative repeater station capable of regenerating optical signals can be arranged is possible; determining a combination of sections judged to be capable of performing transmission that enables a transmission of optical signals from the transmission end to the reception end; and making both ends of respective sections of the determined combination be the relay stations where the regenerative repeater station is arranged, wherein the judging includes a judgment condition which is satisfied in a section including sections but unsatisfied in one of the sections. | 12-01-2011 |
| 20120121258 | METHOD, APPARATUS, AND SYSTEM FOR TRANSMITTING INFORMATION IN PASSIVE OPTICAL NETWORK - A method, an apparatus, and a system for transmitting information in a passive optical network are provided. The method mainly includes: obtaining OAM information that an RE device needs to report to an OLT device, performing modulation processing, according to the OAM information, on a downlink optical signal sent by the OLT device, and returning the downlink optical signal after the modulation processing to the OLT device; or, obtaining OAM information that an OLT device needs to deliver to an RE device, performing modulation processing, according to the OAM information, on a downlink optical signal sent by the OLT device to the RE device, and sending the downlink optical signal after the modulation processing to the RE device. | 05-17-2012 |
| 20120141122 | OPTICAL RECEIVER WITH MONOLITHICALLY INTEGRATED PHOTODETECTOR - An optical receiver includes a photodetector for detecting incoming optical data signals and an amplifier for providing signal gain and current to voltage conversion. The detection signal generated by the photodetector may include a distortion component caused by an operating characteristic of the photodetector. A signal compensating circuit may reconstruct the received optical data signal by effectively canceling the distortion component. For this purpose, the signal compensating circuit may include a decision feedback equalizer implemented using at least one feedback filter matched to the operating characteristic of the photodetector causing the signal distortion so as to reproduce the distortion component for cancellation. Use of a control module may also configure the optical receiver in real time to account for other operating and environmental conditions of the optical receiver. Data rates in excess of 5 Gbps may be realized in monolithic CMOS photodetectors when the signal compensating circuit is properly matched. | 06-07-2012 |
| 20120148237 | Quantum Repeater And System And Method For Creating Extended Entanglements - A method is provided of creating an end-to-end entanglement ( | 06-14-2012 |
| 20120155864 | ADAPTIVE POWER EFFICIENT RECEIVER ARCHITECTURE - Systems and methods for processing an optical signal are disclosed. The optical signal is converted to a voltage signal and the voltage signal is amplified. In addition, a signal strength and/or a signal quality parameter is monitored and an indication of the signal strength and/or a signal quality parameter is generated. Further, a gain and/or an operating bandwidth on the conversion or the amplification can be adjusted based on the indication to reduce power consumption of an optical receiver. | 06-21-2012 |
| 20120177367 | METHOD AND APPARATUS FOR ADJUSTING THE GAIN OF AN AMPLIFIER OF AN OPTICAL RECEIVER MODULE BASED ON LINK BIT ERROR RATE (BER) MEASUREMENTS - An open loop gain adjustment method and apparatus are provided for adjusting the gain of a TIA of an optical RX module based on measurements of the BER of the optical link in which the optical RX module is employed. The gain of the TIA is adjusted until a determination is made that a satisfactory or optimum link BER has been achieved. | 07-12-2012 |
| 20120237215 | TERRESTRIAL OPTICAL FIBER COMMUNICATION WITH ADDED CAPACITY - An optical communication system comprising an optical fiber connected to a first signal regeneration node located at a first end of the optical fiber and a second signal regeneration node located at a second end of the optical fiber; intermediary nodes located between the first and second signal regeneration nodes, wherein one or more pairs of adjacent intermediary nodes each define a span distance along the optical fiber; and one or more Raman amplifiers located within each span distance along the optical fiber, wherein at least one of the one or more Raman amplifiers comprises a case that encases one or more lasers and a temperature controller comprising a temperature sensor to monitor a temperature of the one or more lasers; and a temperature regulator to control a temperature of the one or more lasers. | 09-20-2012 |
| 20130028599 | REPEATER, RELAY METHOD AND OPTICAL TRANSMISSION SYSTEM - There is provided a repeater to relay an optical signal transmitted/received between an optical line terminal (OLT) and at least one optical network unit (ONU), the repeater including: a first port configured to receive an optical signal input from the at least one ONU; a converter circuit configured to convert an optical signal of a first transmission rate into an optical signal of a second transmission rate higher than the first transmission rate, the optical signal of the first transmission rate to be converted being included in optical signals received at the first port; and a second port configured to output the optical signal converted by the converter circuit to the OLT. | 01-31-2013 |
| 20130058646 | ASE COMPENSATION IN OPTICAL AMPLIFIERS - A method of operating a production optical amplifier comprises determining a training data set of amplified spontaneous emission (ASE) values of a training optical amplifier over a plurality of training operating conditions, determining a production data set of ASE values of the production optical amplifier over a plurality of production operating conditions, the plurality of production operating conditions corresponding to a sub-set of the plurality of training operating conditions, determining an adjusted data set of adjusted ASE values produced by extrapolation from the production data set so that the adjusted data set is provided over a plurality of operating conditions corresponding to the plurality of training operating conditions, determining, for each of a plurality of operating conditions, a dynamic ASE tilt factor from the training data set and the adjusted ASE data set so determined, determining a larger data set of ASE values over a wider set of operating conditions than either the training data set or the production data set from the adjusted ASE dataset and the dynamic ASE tilt factor, and compensating the optical output power of the production optical amplifier in correspondence with the larger ASE data set generated from the production data set and the dynamic ASE tilt factor over the plurality of operating conditions, which is preferably a larger set of operating conditions than that of the training data set or production data set. Advantageously a compensating ASE value can be more quickly and cheaply determined by this method compared to those shown in the prior art. | 03-07-2013 |
| 20130279905 | Noise Discriminator for Passive Optical Network Burst Mode Receiver - A noise discriminator circuit and a noise discrimination method in a burst mode receiver is configured to determine the validity of an incoming burst signal by analyzing the timing of the signal edges of incoming signal to look for a time duration conforming to the preamble data bits of a valid burst signal. In one embodiment, the noise discriminator circuit and method analyze the time duration between signal edges of the same pulse of an incoming signal. In another embodiment, the noise discriminator circuit and method analyze the time duration between a first set of pulses of an incoming signal and the time duration between signal edges of a second set of pulses of the incoming signal. When the time durations are within a given time range relating to a predetermined timing separation of a valid burst signal, the incoming signal is validated as a valid burst signal. | 10-24-2013 |
| 20130322875 | OPTICAL TRANSMISSION DEVICE, OPTICAL TRANSMISSION SYSTEM, OPTICAL TRANSMISSION METHOD AND PROGRAM - An optical transmission device according to the present invention comprises: a Raman amplification means; a main signal light sending means which sends first main signal light; a communication interruption detection light monitoring means which sends a first signal if it cannot detect communication interruption detection light; a main signal light monitoring means which sends a second signal if it cannot detect second main signal light; a light monitoring signal analysis means which sends a result of its analysis of a light monitoring signal as a third signal in a predetermined period of time; and a control means which makes the Raman amplification means suspend the generation of the excitation light, if it cannot receive the third signal even after the elapse of the predetermined period of time in the state it has received the first signal and has not received the second signal, and stops sending of the first main signal light from the main signal light sending means when receiving the second signal further. | 12-05-2013 |
| 20150016819 | Self-Tuning an Optical Network at an Operating Point - Techniques are presented for automatic tuning of operating parameters, e.g., amplifier gain, in an optical network. A section of an optical network comprises a plurality of spans between optical nodes, and each optical node has an amplifier to amplify optical signals for transmission between optical nodes. Physical network layer data is obtained from the optical nodes for use as input to an analytical model. A set of powers defining an optimum working point of the amplifiers is computed based on variations in amplifier noise figure which depend on amplifier gain. A figure of merit representative of network section performance is computed based on linear and non-linear noise at current power levels of the amplifiers. The figure of merit is evaluated. The set of powers is applied to the amplifiers in the network section when evaluation of the figure of merit indicates that network performance improvement can be achieved. | 01-15-2015 |
| 20150086197 | PHOTODETECTION DEVICE, PHOTODETECTION METHOD, AND OPTICAL TRANSMISSION DEVICE - The light reception unit is disposed behind each of a plurality of light sources that emits signal lights having mutually different wavelengths in a forward direction and receives a backlight emitted backward from each of the light sources. The synchronizing signal generation unit generates a synchronizing signal serving as an electric signal synchronized in phase with a drive signal for driving each of the light sources. The multiplication unit multiplies the synchronizing signal and a light reception signal serving as an electric signal obtained by receiving the backlight by the light reception unit. The light power detection unit detects power of the signal light by multiplying an integrated value of a multiplication signal obtained by multiplying the synchronizing signal and the light reception signal by the multiplication unit and a power ratio of the signal light to the backlight stored in a predetermined storage unit. | 03-26-2015 |
| 20150381287 | Light Receiving Circuit, Optical Transceiver, And Received Output Waveform Cross Point Controlling Method - A light-receiving circuit includes an optical-to-electrical transduction element, a TIA processing section to output a voltage in proportion to a current input from the optical-to-electrical transduction element, and a control section to control the TIA processing section. The TIA processing section includes a TIA, which generates the voltage output signal in proportion to the current input from the optical-to-electrical transduction element, an amplifier, which amplifies the output signal of the TIA, a monitoring portion, which monitors the current to be input to the TIA, and an offset-adjusting portion provided between the TIA and the amplifier to adjust and output an offset level of the output signal of the TIA to the amplifier. The control section acquires a value of the current to be input from the monitoring portion to the TIA, and controls the offset-adjusting portion so as to adjust the offset level in proportion to that acquired current value. | 12-31-2015 |
| 20160006517 | BURST-MODE RECEIVER, AND METHOD OF BIAS VOLTAGE CONTROL FOR APD OF BURST-MODE RECEIVER - A burst-mode receiver for receiving burst optical signals having different intensities by a reversely connected APD, including: a current detection circuit outputting a photocurrent that is generated by APD and is output from a current mirror circuit (CMC) as a voltage proportional to the photocurrent, the CMC being connected in series between a power supply and APD; a peak detector circuit detecting and holding a peak value of the output voltage of the current detection circuit; a resistor connection switching circuit, which is inserted between the CMC and APD, for connecting a series resistor to APD in series by switching; and a comparator outputting a switching signal for switching the resistor connection switching circuit so that the series resistor is connected to APD in series in a case where a voltage detected by the peak detector circuit is equal to or more than a predetermined threshold. | 01-07-2016 |
| 20160065320 | DETERMINING PROPAGATION DELAY OF COMMUNICATIONS IN DISTRIBUTED ANTENNA SYSTEMS, AND RELATED COMPONENTS, SYSTEMS, AND METHODS - Components, systems, and methods for determining propagation delay of communications in distributed antenna systems are disclosed. The propagation delay of communications signals distributed in the distributed antenna systems is determined. If desired, the propagation delay(s) can be determined on a per remote antenna unit basis for the distributed antenna systems. The propagation delay(s) can provided by the distributed antenna systems to a network or other system to be taken into consideration for communications services or operations that are based on communications signal delay. As another non-limiting example, propagation delay can be determined and controlled for each remote antenna unit to uniquely distinguish the remote antenna units. In this manner, the location of a client device communicating with a remote antenna unit can be determined within the communication range of the remote antenna unit. | 03-03-2016 |
