Receiver Patents (Class 398/202)
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Publication number: 20150147070Abstract: A communication method in the present disclosure is a communication method for obtaining information from a subject, including: taking a picture of the subject in a picture-taking mode, thereby obtaining image data; performing, after the taking, visible light communication in a visible light communication mode which is a different mode from the picture-taking mode, thereby obtaining visible light data of the subject; and embedding the visible light data obtained, into the image data, and thus saving the visible light data obtained.Type: ApplicationFiled: June 5, 2014Publication date: May 28, 2015Applicant: Panasonic CorporationInventors: Mitsuaki OSHIMA, Koji NAKANISHI, Hideki AOYAMA, Chikara YOSHIDA, Shigehiro IIDA, Shinsuke OGATA, Kengo MIYOSHI
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Patent number: 9042737Abstract: In the present invention, wasted power consumption caused when a clock and data recovery unit in an optical network unit in a PON system is activated from a power-saving state is reduced and rapid, secure communication is performed. A clock and data recovery unit includes a phase-locked loop that can be set to normal mode or power-saving mode and that includes a voltage-controlled oscillator and recovers a clock signal and a data signal from input signals. The clock and data recovery unit includes a reference clock multiplier circuit that multiplies a reference clock signal and outputs the multiplied reference clock signal; and a frequency training loop that includes the same voltage-controlled oscillator and performs synchronous oscillation training by the voltage-controlled oscillator using the reference clock multiplier circuit before the phase-locked loop transitions from power-saving mode to normal mode.Type: GrantFiled: February 21, 2012Date of Patent: May 26, 2015Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventor: Naruto Tanaka
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Patent number: 9042820Abstract: An optical receiver circuit is disclosed in which a number of electrical signals are processed to extract data encoded therein. The electrical signals may be compared during the process to selectively remove one or more waveforms from one or more corresponding electrical signals. Various data signals, each including one or more waveforms, may then be processed to extract the encoded data. The optical receiver circuit reduces, or eliminates, electrical offsets which may be present in one or more of the electrical signals to reduce corresponding errors in the encoded data signals.Type: GrantFiled: May 28, 2010Date of Patent: May 26, 2015Assignee: Infinera CorporationInventors: Huan-Shang Tsai, Jeffrey T. Rahn
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Patent number: 9042741Abstract: Described herein are systems and methods for accurately estimating and removing a carrier frequency offset. One exemplary embodiment relates to a system comprising a frequency offset detection circuit detecting a carrier frequency offset in an optical signal, and a frequency testing circuit calculating an estimated frequency offset value of the carrier frequency offset, wherein the frequency testing circuit removes a carrier phase based on the estimated frequency offset value and recovers the optical signal. Another exemplary embodiment relates to a method comprising detecting a carrier frequency offset in an optical signal, calculating an estimated frequency offset value of the carrier frequency offset, removing a carrier phase based on the estimated frequency offset value, and recovering the optical signal.Type: GrantFiled: March 15, 2011Date of Patent: May 26, 2015Assignee: AT&T INTELLECTUAL PROPERTY I, L.P.Inventor: Xiang Zhou
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Publication number: 20150139666Abstract: A multi-wavelength optical signal receiving apparatus receives a multi-wavelength optical signal, demultiplexes the received optical signal to convert into an electric signal. The multi-wavelength optical signal receiving apparatus includes a demultiplexing part including a demultiplexer configured to divide the received multi-wavelength optical signal into a plurality of optical signals by wavelength, a photoelectric conversion part to convert the optical signals into electric signals and amplify the electric signals, and at least one lower securing plate configured to couple the parts by an active alignment method. Accordingly, an additional polishing or coating process is not required, which simplifies the manufacturing process, and it is possible to manufacture the apparatus in blocks, thereby increasing mass-productivity.Type: ApplicationFiled: August 25, 2014Publication date: May 21, 2015Inventors: JOON KI LEE, SAE KYOUNG KANG, JOON YOUNG HUH
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Patent number: 9036999Abstract: One aspect provides an optical communication system. The system includes an optical-to-digital converter, a frequency estimator and a symbol synchronizer. The optical-to-digital converter is configured to receive an optical OFDM bit stream including an OFDM symbol bearing payload data and a symbol header preceding the OFDM payload data. The frequency estimator is configured to determine a carrier frequency offset of the payload data from the symbol header. The symbol synchronizer is configured to determine a starting location of the payload data within the bit stream by cross-correlating a synchronization pattern within the symbol header with a model synchronization pattern stored by the symbol synchronizer.Type: GrantFiled: July 29, 2011Date of Patent: May 19, 2015Assignee: Alcatel LucentInventors: Noriaki Kaneda, Timo Pfau, Qi Yang
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Patent number: 9025969Abstract: An optical signal receiver tracks local oscillator frequency offset (LOFO) and compensates for the phase distortion introduced in the received signals as a result of utilizing the local oscillator within a coherent detection scheme. This phase distortion is basically a constant phase rotation caused by the LOFO and implementation of the receiver using coherent detection and a digital interferometer instead of a conventional (yet complex) carrier phase estimation or recovery scheme. With an optical receiver implemented in this manner, the requirement of using a precise local oscillator laser with low frequency offset is less important.Type: GrantFiled: May 24, 2012Date of Patent: May 5, 2015Assignee: Futurewei Technologies, Inc.Inventors: Chuandong Li, Yuanjie Chen, Zhuhong Zhang, Yi Cai, Fei Zhu
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Patent number: 9025970Abstract: A comparator (11) outputs, out of an electrical signal input from a trans impedance amplifier (TIA) via a coupling capacitor, pulses having amplitudes equal to or larger than a reference value as a comparison output signal (Cout). An analog holding circuit (12) charges a holding capacitor with each pulse contained in the comparison output signal (Cout) and also removes a DC voltage obtained by the charging via a discharging resistor, thereby generating a holding output signal (Hout) that changes in accordance with the presence/absence of input of an optical signal. This allows to perform an autonomous operation without any necessity of an external control signal and properly detect the presence/absence of input of an optical signal.Type: GrantFiled: February 14, 2011Date of Patent: May 5, 2015Assignees: Nippon Telegraph and Telephone Corporation, NTT Electronics CorporationInventors: Hiroshi Koizumi, Kazuyoshi Nishimura, Masafumi Nogawa, Yoshikazu Urabe
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Patent number: 9025967Abstract: All-optical phase-modulated data signal regenerator apparatus (10) comprising an optical input (12), an optical signal converter (16), an optical carrier signal source (18), optical signal forming apparatus (20) and an optical output (14). The input (12) is arranged to receive a phase-modulated optical data signal. The signal converter (16) is arranged to receive the data signal and to convert phase modulation of the data signal into a corresponding intensity modulation of an intermediate optical signal. The carrier signal source (18) provides an optical carrier signal.Type: GrantFiled: December 10, 2009Date of Patent: May 5, 2015Assignee: Telefonaktiebolaget L M Ericsson (publ)Inventor: Ernesto Ciaramella
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Publication number: 20150117871Abstract: An optical level control apparatus includes an input port, an output port, an optical device to assume a state of outputting light inputted to the input port from the output port and a state of not outputting the light inputted to the input port from the output port; a detector to detect an intensity of the light inputted to the input port, and a control unit to detect an input of an optical burst signal to the input port on the basis of a result of detecting the intensity of the light and to control the optical device so that the signal, in which to eliminate a field extending up to an elapse of a period of first time equal to or shorter than laser ON time period of the signal from a head of the signal with its input being detected, is output from the output port.Type: ApplicationFiled: September 30, 2014Publication date: April 30, 2015Applicant: FUJITSU LIMITEDInventors: Setsuo YOSHIDA, Keisuke Harada
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Publication number: 20150117870Abstract: Disclosed are a method and device for increasing the adaptability of light intensity, which relate to the field of photoelectric communications. The method comprises: providing several stages of load resistors in the device, the device collecting voltage values, calculating the average value of all the collected voltage values when a preset number of voltage values which meet the requirements are collected, setting a voltage according to the average value and judging whether the set voltage meets preset requirements; and if yes, collecting data according to the set voltage; otherwise switching a load resistor according to a preset rule, wherein the load voltage may affect the voltage collection. The present invention has the beneficial effects of: improving the adaptability of a screen to light intensity during optical signal collection, and at the same time being able to reduce the error rate.Type: ApplicationFiled: December 25, 2012Publication date: April 30, 2015Inventors: Zhou Lu, Huazhang Yu
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Patent number: 9020364Abstract: In one embodiment, an optical receiver has a bulk dispersion compensator and a butterfly equalizer serially connected to one another to perform dispersion-compensation processing and electronic polarization de-multiplexing. The bulk dispersion compensator has a relatively large dispersion-compensation capacity, but is relatively slow and operates in a quasi-static configuration. The butterfly equalizer has a relatively small dispersion-compensation capacity, but can be dynamically reconfigured on a relatively fast time scale to track the changing conditions in the optical-transport link. The optical receiver has a feedback path that enables the configuration of the bulk dispersion compensator to be changed based on the configuration of the butterfly equalizer in a manner that advantageously enables the receiver to tolerate larger amounts of chromatic dispersion and/or polarization-mode dispersion than without the use of the feedback path.Type: GrantFiled: September 27, 2012Date of Patent: April 28, 2015Assignee: Alcatel LucentInventors: Chongjin Xie, Peter J. Winzer, Stefan Weisser, Andreas Leven
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Patent number: 9014566Abstract: An optical component contains a tunable laser. The tunable laser provides an optical local oscillator signal, and the tunable laser is directly modulated to provide a modulated optical data signal. In this manner we have optimization of the channel wavelength and obtain an optimized electrical and optical bandwidth utilization. Furthermore, a method for data processing is suggested.Type: GrantFiled: October 6, 2008Date of Patent: April 21, 2015Assignee: Xieon Networks S.a.r.l.Inventor: Erich Gottwald
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Method and apparatus for simulating a photon-counting detector array as used in a communication link
Patent number: 9014551Abstract: The method and apparatus as disclosed herein allows the user to input conditions for a communications link, set characteristic values of a photon-counting detector array, simulate the resulting link, observe a summary analysis of the simulated detector and link activity, and extract a record of the detector activity (e.g. each photon counted) making it available for further analysis.Type: GrantFiled: March 13, 2013Date of Patent: April 21, 2015Assignee: The United States of America as Represented by the Secretary of the Air ForceInventor: Adam M. Stooke -
Publication number: 20150104188Abstract: An active optical beam shaping system includes a first deformable mirror arranged to at least partially intercept an entrance beam of light and to provide a first reflected beam of light, a second deformable mirror arranged to at least partially intercept the first reflected beam of light from the first deformable mirror and to provide a second reflected beam of light, and a signal processing and control system configured to communicate with the first and second deformable mirrors. The first deformable mirror, the second deformable mirror and the signal processing and control system together provide a large amplitude light modulation range to provide an actively shaped optical beam.Type: ApplicationFiled: October 11, 2013Publication date: April 16, 2015Applicant: The Johns Hopkins UniversityInventors: Colin A. Norman, Laurent A. Pueyo
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Publication number: 20150104198Abstract: A completely digital optical receiver is provided. The optical receiver includes a photodiode configured to provide a photodiode output responsive to an on-off keyed (OOK) optical input. Two or more digital inverters connected in series with each other are configured to receive the photodiode output and provide an amplified digital output. A digital clock and data recovery (CDR) circuit receives the amplified digital output and provides a clock output and a data output. A digital photodiode discharging circuit is connected to the photodiode and controlled by the clock output of the CDR circuit.Type: ApplicationFiled: December 19, 2014Publication date: April 16, 2015Inventors: Harmen Joseph Sebastiaan Dorren, Oded Raz
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Patent number: 9008521Abstract: Provided is an optical receiver including a first delay interferometer, a second delay interferometer, and an input light splitting portion for inputting modulated light. The first delay interferometer includes a first light splitting portion for splitting the input light into first light and second light, a first reflecting portion and a second reflecting portion for causing the first light and the second light to return to the first light splitting portion. The second delay interferometer includes a second light splitting portion for splitting the input light into third light and fourth light, a third reflecting portion and a fourth reflecting portion for causing the third light and the fourth light to return to the second light splitting portion. A region between the first light splitting portion and the second reflecting portion intersects with a region between the second light splitting portion and the fourth reflecting portion.Type: GrantFiled: July 10, 2013Date of Patent: April 14, 2015Assignee: Oclaro Japan, IncInventors: Koki Iemura, Takuma Ban, Hideharu Mikami, Kentaro Osawa
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Publication number: 20150098713Abstract: In a coherent optical receiver, sufficient demodulation becomes impossible and consequently receiving performance deteriorates if an inter-channel skew arises, therefore, a coherent optical receiver according to an exemplary aspect of the invention includes a local light source, a 90° hybrid circuit, an optoelectronic converter, an analog to digital converter, and a digital signal processing unit; wherein the 90° hybrid circuit makes multiplexed signal light interfere with local light from the local light source, and outputs a plurality of optical signals separated into a plurality of signal components; the optoelectronic converter detects the optical signals and outputs detected electrical signals; the analog to digital converter quantizes the detected electrical signals and outputs quantized signals; the digital signal processing unit includes a skew compensation unit for compensating a difference in propagation delay between the plurality of signal components, and an FFT operation unit for performing a fasType: ApplicationFiled: December 19, 2014Publication date: April 9, 2015Applicant: NEC CORPORATIONInventors: Junichi ABE, Wakako YASUDA, Kiyoshi FUKUCHI
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Publication number: 20150093118Abstract: In an optical communication system, an optical transmitter changes operational physical layer parameters to meet future target throughput for the optical communication system. The optical transmitter communicates the upcoming change to the optical receiver in a message that used current physical layer parameters. The optical transmitter provides sufficient time to the optical receiver to adjust reception functions of the receiver, including polarization based demodulation scheme. In some implementations, the optical transmitter performs the transition to a new physical layer transmission format without waiting for an acknowledgement from the optical receiver.Type: ApplicationFiled: September 30, 2014Publication date: April 2, 2015Inventors: Zhensheng Jia, Yi Cai, Hung-Chang Chien, Jianjun Yu
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Patent number: 8995836Abstract: A wavelength division multiplexing passive optical network (WPON) comprising an optical line terminal (OLT) and a plurality of optical network units (ONUs) coupled to the OLT via a power optical splitter. The OLT is configured to monitor wavelengths in use by the ONUs and to divide upstream traffic from the ONUs into multiple channels using tunable filters. Also disclosed is an OLT for a PON, the OLT comprising a plurality of receivers and a plurality of tunable filters corresponding to each of the receivers. The OLT also comprises channel control logic coupled to the tunable filters, wherein the channel control logic is configured to detect a plurality of wavelengths in use for upstream traffic in the PON and to divide the upstream traffic into multiple channels using the tunable filters. Included is a method for managing upstream traffic in a PON, the method comprising monitoring, by a processor, wavelengths in use for upstream traffic in the PON.Type: GrantFiled: July 11, 2011Date of Patent: March 31, 2015Assignee: Futurewei Technologies, Inc.Inventors: Ning Cheng, Frank J. Effenberger, Guo Wei
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Patent number: 8989575Abstract: The present invention provides a signal detection method, including: receiving, by a frequency mixer, wavelength division multiplexing signals and a local oscillator signal, where a wavelength of the local oscillator signal and a wavelength of a target signal in the wavelength division multiplexing signals are the same; a frequency mixer performs interference on the wavelength division multiplexing signals through the local oscillator signal to obtain a coherent signal formed by the local oscillator signal and the target signal; sending the coherent signal to a transimpedance amplifier for amplification to obtain a voltage signal; and obtaining the power of the target signal according to a power amplitude of the voltage signal.Type: GrantFiled: August 29, 2012Date of Patent: March 24, 2015Assignee: Huawei Technologies Co., Ltd.Inventors: Haitao Ye, Shuangyuan Wu, Weijian Chen, Yongzhong Wang
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Patent number: 8989300Abstract: An optical communication system, a transmitter, a receiver, and methods of operating the same are provided. In particular, a transmitter is disclosed as being configured to encode optical signals in accordance with a multi-level coding scheme. The receiver is configured to provide receive and decode to the optical signals received from the transmitter. One or both of the receiver and transmitter are configured to compensate for non-idealities or non-linearities introduced into the communication system by optical components of the system.Type: GrantFiled: February 6, 2014Date of Patent: March 24, 2015Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.Inventors: Georgios Asmanis, Faouzi Chaahoub, Michael Allen Robinson, David W. Dolfi
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Patent number: 8989602Abstract: A digital coherent optical receiver includes a processor that is operative to separate electric signals obtained by converting an optical signal into a horizontal signal component and a vertical signal component; to generate a histogram of the horizontal signal component and the vertical signal component as outputs of the equalizing filter; and to determine a presence/absence of local convergence based on distribution of the histogram of the horizontal signal component and the histogram of the vertical signal component.Type: GrantFiled: October 27, 2011Date of Patent: March 24, 2015Assignee: Fujitsu LimitedInventors: Kosuke Komaki, Osamu Takeuchi
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Patent number: 8989604Abstract: An optical receiver is provided with a photoelectric converter that outputs an electrical signal according to light that is received by a light-receiving region. The optical receiver is provided with a condensing lens and optical filter that are located in an optical path from where signal light enters towards the light-receiving region. The condensing lens condenses the signal light onto the light-receiving region. The optical filter reflects light having a first wavelength that is included in the signal light using a front surface thereof and reflects light having a second wavelength that is included in the signal light using a rear surface thereof that faces the front surface so that the light is emitted through the front surface.Type: GrantFiled: September 12, 2012Date of Patent: March 24, 2015Assignee: Mitsubishi Electric CorporationInventors: Nobuo Ohata, Mizuki Shirao, Keita Mochizuki
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Publication number: 20150078765Abstract: To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus.Type: ApplicationFiled: November 21, 2014Publication date: March 19, 2015Inventors: Koichi Ishihara, Takayuki Kobayashi, Riichi Kudo, Yasushi Takatori, Munehiro Matsui, Masato Mizoguchi, Akihide Sano, Shogo Yamanaka, Etsushi Yamazaki, Yutaka Miyamoto, Eiji Yoshida, Tadao Nakagawa
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Patent number: 8983300Abstract: A system and a method are disclosed for receiving an infrared signal on a mobile device. The mobile device receives an infrared signal by creating an intermediate bitstream based on the received infrared signal. The intermediate bitstream is trimmed, downsampled, and demodulated in the time domain. The intermediate bitstream is then converted into a raw infrared code. The received bitstream is processed in a software layer, enabling the mobile device to process infrared signals without the use of additional hardware configured on the mobile device.Type: GrantFiled: May 6, 2014Date of Patent: March 17, 2015Assignee: Peel Technologies, Inc.Inventors: Samyeer Suresh Metrani, Siva Subramanian Muthukumarasamy
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Patent number: 8983302Abstract: An apparatus comprises an optical transmitter; an optical detector configured to receive optical signals from an optical fiber; an optical splitter having a first port, a second port coupled to the optical detector by the optical fiber, and a third port coupled to the optical transmitter; and a two stage amplifier system connected to an output of the optical detector. An input surface of the optical detector may have a diameter that is substantially equal to a diameter of a core in the optical fiber. The diameter of the input surface of the optical detector reduces capacitance and reduces signal distortion. The optical splitter may be configured to receive a first optical signal at the first port. The optical splitter may be configured to send the first optical signal to the second port and send a second optical signal received at the third port to the first port.Type: GrantFiled: November 5, 2009Date of Patent: March 17, 2015Assignee: The Boeing CompanyInventor: Eric Yuen-Jun Chan
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Patent number: 8983308Abstract: In general, this disclosure relates to optical network devices with support for multiple physical layer transport standards. An optical network device may include an optical receiver that can be adaptively configured to support different physical layer transport standards. For example, the optical receiver may include a photodiode and a control unit to adjust a characteristic of the photodiode to support different optical physical layer transport standards on an adaptive basis. For example, the control unit may adjust the photodiode characteristic to prevent an overload condition when an optical signal is received according to the physical layer access standard.Type: GrantFiled: September 22, 2009Date of Patent: March 17, 2015Assignee: Calix, Inc.Inventors: Mark R. Biegert, Peter O. Lee
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Patent number: 8983309Abstract: A transmitter in an optical communications system includes a digital signal processor for processing a data signal to generate a sample stream encoding successive symbols in accordance with a constrained phase modulation scheme having a constellation of at least two symbols and a modulation phase constrained to a phase range spanning less than 4?. A digital-to-analog converter converts the sample stream into a corresponding analog drive signal. A finite range phase modulator modulates a phase of a continuous wavelength channel light in accordance with the analog drive signal, to generate a modulated channel light for transmission through the optical communications system. A receiver in the optical communications system includes an optical stage for detecting phase and amplitude of the modulated channel light and for generating a corresponding sample stream, and a digital signal processor for processing the sample stream to estimate each successive symbol of the modulated channel light.Type: GrantFiled: February 13, 2012Date of Patent: March 17, 2015Assignee: Ciena CorporationInventors: James Harley, Douglas McGhan, Shahab Oveis Gharan, Kim B. Roberts, Mark Rollins
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Patent number: 8977140Abstract: An optical receiver includes: an interference unit generating a first interference light signal (ILS1) and a second interference light signal (ILS2) with an approximately inverse phase to that of the first interference light signal, by causing a received light signal to interfere with local oscillator light; a first interference light subtraction unit generating a first interference light subtraction signal (ILSS1) representing the difference between signals obtained by photoelectric conversion of ILS1 and a local oscillator light proportional signal having light intensity based on the light intensity of the local oscillator light; a second interference light subtraction unit generating a second interference light subtraction signal (ILSS2) representing the difference between a signal obtained by photoelectric conversion of ILS2 and the signal obtained by photoelectric conversion of the local oscillator light proportional signal; and a difference output unit outputting a signal representing the difference betType: GrantFiled: February 17, 2012Date of Patent: March 10, 2015Assignee: NEC CorporationInventor: Yasuyuki Suzuki
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Patent number: 8977141Abstract: A parameter of an adaptive filter is optimized so that inter-symbol interference having an amount corresponding to an inserted fixed filter remains.Type: GrantFiled: February 7, 2012Date of Patent: March 10, 2015Assignee: Nippon Telegraph and Telephone CorporationInventors: Kengo Horikoshi, Etsushi Yamazaki, Takayuki Kobayashi, Eiji Yoshida, Yutaka Miyamoto
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Patent number: 8965211Abstract: A system and method of digitizing an analog signal without an amplitude channel is disclosed. The system and method includes receiving an analog signal comprising a voltage v(t) and a frequency f1, producing a series of optical pulses at a sampling frequency f2 with a pulsed laser, splitting the series of optical pulses into a first optical signal and an optical reference signal, phase modulating the first optical signal with the analog signal to produce a sampled optical signal such that phase shifts between adjacent samples in the sampled optical signal does not exceed ? radians, and receiving the sampled optical signal and the optical reference signal at a photonic signal processor.Type: GrantFiled: September 29, 2011Date of Patent: February 24, 2015Assignee: Rockwell Collins, Inc.Inventors: Raymond Zanoni, Kim S. Jepsen, Oliver S. King, Mark A. Laliberte
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Patent number: 8965200Abstract: A method, an apparatus and a system for detecting a connection status of an optical fiber jumper are provided in the embodiments of the present invention. The method for detecting a connection status of an optical fiber jumper includes: judging a connection status of a second port and a first port according to whether an optical signal sent by the first port to the second port through a first optical fiber is received, wherein the first optical fiber is connected to two ends of an optical fiber jumper, and the two ends of the optical fiber jumper are connected to the first port and the second port respectively; and obtaining a port identification corresponding to the first port according to the optical signal if the optical signal is received.Type: GrantFiled: November 21, 2011Date of Patent: February 24, 2015Assignee: Huawei Technologies Co., Ltd.Inventors: Yunsheng Wen, Jun Zhao, Bo Wang, Xiaolei Shan
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Patent number: 8965218Abstract: According to one embodiment, a photo detector-combined illuminance sensor includes a circuit for a Photo Detector (PD) function to detect the illuminance of the ambient environment. The illuminance sensor operates under the control of a controller in a visible light communication terminal. When an optical signal detected by the illuminance sensor is a visible light communication signal, the controller switches to cause the illuminance sensor to operate as the photo detector for the visible light communication in a visible light communication mode.Type: GrantFiled: July 12, 2012Date of Patent: February 24, 2015Assignee: Samsung Electronics Co., Ltd.Inventors: Jae-Seung Son, Tae-Han Bae, Eun-Tae Won
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Patent number: 8958706Abstract: A coherent optical communication device includes a demodulator configured to demodulate a reception signal; a local oscillator light optical source configured to generate local oscillator light used for demodulating the reception signal; a memory configured to store wavelength information; and a controller configured to control the local oscillator light optical source when the demodulator cannot receive the reception signal, so that a wavelength of the local oscillator light generated in the local oscillator light optical source is changed to a wavelength specified by the wavelength information stored in the memory.Type: GrantFiled: January 25, 2011Date of Patent: February 17, 2015Assignee: Fujitsu LimitedInventor: Takuji Maeda
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Patent number: 8958701Abstract: A method, a network, and a node each implement the transmission of Automatic Protection Switching (APS) switching coordination bytes across an OTN network. A working signal and a protection signal are received, one of which is designated as an active signal. The active signal is encapsulated in an Optical channel Data Unit (ODU) signal. APS switching coordination bytes from the working and protection signals are placed in an overhead segment of the ODU signal. The ODU signal is transmitted into and received from an Optical Transport Network (OTN) network. The working and protection signals are recreated based on the active signal encapsulated in the ODU signal and the APS switching coordination bytes in the overhead segment. The recreated working and protection signals are transmitted. In this manner, a single ODU signal may be used to transmit both the working and protection signals.Type: GrantFiled: December 27, 2012Date of Patent: February 17, 2015Assignee: Ciena CorporationInventors: Abhishek Chaudhary, Hongxing Meng, Satish Gopalakrishna
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Publication number: 20150043926Abstract: A method for performing blind channel estimation for an MLSE receiver in a communication channel, according to which Initial Metrics Determination Procedure (IMDP) is performed using joint channel and data estimation in a decision directed mode. This is done by generating a bank of initial metrics that assures convergence, based on initial coarse histograms estimation, representing the channel and selecting a first metrics set M from the predefined bank. Then an iterative decoding procedure is activated during which, a plurality of decision-directed adaptation learning loops are carried out to perform an iterative histograms estimation procedure for finely tuning the channel estimation. Data is decoded during each iteration, based on a previous estimation of the channel during the previous iteration. If convergence is achieved, ISI optimization that maximizes the amount of ISI that is compensated by the MLSE is performed.Type: ApplicationFiled: August 7, 2014Publication date: February 12, 2015Inventors: Omri Levy, Gilad Katz, Albert Gorshtein, Dan Sadot
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Patent number: 8953945Abstract: A radio transmitter integrated circuit includes a photodiode array circuit, a digital conversion module, and a transmit baseband processing module. The photodiode array circuit converts received light into electrical image signals. The digital conversion module converts the electrical image signals into digital image signals. The transmit baseband processing module converts the digital image signals into digital transmit baseband or low IF signals.Type: GrantFiled: November 15, 2010Date of Patent: February 10, 2015Assignee: Broadcom CorporationInventor: Ahmadreza (Reza) Rofougaran
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Patent number: 8953947Abstract: In some examples, a transmit assembly is described that may include a first optical transmitter, a second optical transmitter, and a polarizing beam combiner. The first optical transmitter may be configured to emit a first optical data signal centered at a first frequency. The second optical transmitter may be configured to emit a second optical data signal centered at a second frequency offset from the first frequency by a nominal offset n. The polarizing beam combiner may be configured to generate a dual carrier optical data signal by polarization interleaving the first optical data signal with the second optical data signal. An output of the polarizing beam combiner may be configured to be communicatively coupled via an optical transmission medium to a polarization-insensitive receive assembly.Type: GrantFiled: April 24, 2012Date of Patent: February 10, 2015Assignee: Finisar CorporationInventors: Ilya Lyubomirsky, Yasuhiro Matsui, Daniel Mahgerefteh
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Patent number: 8953951Abstract: This disclosure describes the Fast Chromatic Dispersion Estimation (FCDE) techniques which corrects for chromatic dispersion in high data rate optical communications systems such as some coherent optical communications systems. FCDE may utilize transform such as fast-Fourier transforms to estimate the chromatic dispersion. From an estimation of the chromatic dispersion, the techniques may determine filter tap coefficients for compensating the chromatic dispersion.Type: GrantFiled: June 19, 2012Date of Patent: February 10, 2015Assignee: Juniper Networks, Inc.Inventors: Philip A. Thomas, Christian Malouin, Theodore John Schmidt
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Patent number: 8948613Abstract: In part, aspects of the invention relate to methods, apparatus, and systems for intensity and/or pattern line noise reduction in a data collection system such as an optical coherence tomography system that uses an electromagnetic radiation source and interferometric principles. In one embodiment, the noise is intensity noise or line pattern noise and the source is a laser such as a swept laser. One or more attenuators responsive to one or more control signals can be used in conjunction with an analog or digital feedback network in one embodiment.Type: GrantFiled: March 17, 2011Date of Patent: February 3, 2015Assignee: Lightlab Imaging, Inc.Inventors: Joseph M. Schmitt, Victor Grinberg
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Patent number: 8948610Abstract: Methods for receiving a signal and a detection circuit are disclosed. The detection circuit and related methods may be useful for the fast and accurate receiving of data signals. The detection circuit generally comprises a first circuit having a first time constant, a second circuit having (i) a common input with the first circuit and (ii) a second time constant, the second time constant being less than the first time constant, and a switch configured to (i) charge the first circuit with an input signal when the switch is in a first state, and (ii) charge or discharge the second circuit with the input signal when the switch is in a second state, the switch having the second state when the input signal is no longer received at the common input.Type: GrantFiled: October 26, 2011Date of Patent: February 3, 2015Assignee: Source Photonics, Inc.Inventors: Mohammad Azadeh, Near Margalit
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Patent number: 8948611Abstract: A circuit and method for reducing power consumption in an I/R receiver system includes determining a duty cycle of a command cycle comprising a series of command pulses separated by nulls and enabling and disabling selective active components of an I/R receiver system in accordance with the duty cycle. In an embodiment, the enabling of the active components commences during a null prior to the arrival of a new command pulse. In a further example embodiment, the enabling includes first enabling a first set of active components having a first settling time, waiting for at least the first settling time, and then second enabling a second set of active components having a second settling time.Type: GrantFiled: May 31, 2012Date of Patent: February 3, 2015Assignee: Maxim Integrated Products, Inc.Inventors: Andrew Gerald Zocher, Richard Dean Davis, Theron Lee Jones, Luiz Antonio Razera, Jr.
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Publication number: 20150030340Abstract: A method for determining a presence of a locking signal in a signal received by an optical receiver device, the optical receiver device configured to be used in an optical communications network, the locking signal being a signal exchanged by optical communication devices of the optical communications network in a phase preceding setting up communications between the optical communication devices. The presence of the locking signal is determined by obtaining a direct current component or a component at twice a frequency at which the locking signal is supposed to be modulated, and by obtaining a contribution of the communication signal, if any, on the component.Type: ApplicationFiled: January 22, 2013Publication date: January 29, 2015Applicant: MITSUBISHI ELECTRIC CORPORATIONInventor: Gwillerm Froc
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Patent number: 8942572Abstract: A lighting system includes light fixtures not in communications with and not synchronized with one another, and one or more light sensors. Each light fixture separately emits data encoded visible light including light fixture information encoded therein in a manner that avoids visually perceptible flicker and enables light fixture information emitted by one light fixture to be distinguished from light fixture information emitted by other light fixtures. The light fixture information is encoded into data encoded visible light such that a difference between different levels of the data encoded visible light is indicative of an illumination capability of the light fixture and such that visually perceptible flicker is avoided. Each light sensor separately receives portions of data encoded light visible light emitted by multiple light fixtures and separately determines the identity of and the maximum and present illumination contributions for each light fixture.Type: GrantFiled: February 21, 2014Date of Patent: January 27, 2015Inventor: Bret Rothenberg
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Patent number: 8942573Abstract: A device and method are disclosed for blind equalization of an optical signal to implement adaptive polarization recovery, Polarization Mode Dispersion (PMD) compensation, and residual Chromatic Dispersion (CD) compensation in a digital coherent optical communication system.Type: GrantFiled: October 19, 2012Date of Patent: January 27, 2015Assignee: AT&T Intellectual Property I, L.P.Inventor: Xiang Zhou
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Patent number: 8942567Abstract: An optical receiving device includes multiple input ports to which light is input; multiple amplifiers that are arrayed and provided corresponding to the input ports, respectively, each of the amplifiers amplifying and outputting light input from a corresponding input port among of the input ports; a photo diode that converts light into an electrical signal; and a lens that inputs to the photo diode light output from the amplifiers.Type: GrantFiled: December 13, 2011Date of Patent: January 27, 2015Assignee: Fujitsu LimitedInventors: Goji Nakagawa, Susumu Kinoshita
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Publication number: 20150023674Abstract: The present document relates to an optical communication system. In particular, the present document relates to the alignment of the laser frequency at a transmitter of the optical communication system and the local oscillator frequency at a coherent receiver of the optical communication system. A coherent optical receiver (222) is described. The receiver (222) comprises a reception unit adapted to convert a received optical signal at a carrier frequency into a digital signal using a local oscillator, referred to as LO, having an LO frequency; a spectral analysis unit adapted to estimate a degree of asymmetry of a spectrum of the received optical signal, based on the digital signal; and a transmission unit adapted to transmit an indication of the degree of asymmetry to a near-end transponder (210) comprising a transmitter (211) of the received optical signal.Type: ApplicationFiled: February 12, 2013Publication date: January 22, 2015Inventors: Massimiliano Salsi, Oriol Bertran-Pardo
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Patent number: 8936405Abstract: A multi-channel optical receiver module, includes a light-receiving element array, the light-receiving element array including multiple light-receiving elements; an amplifier disposed adjacent the light-receiving element array, the amplifier amplifying an output of a light-receiving element; a wiring relay submount disposed adjacent the amplifier; two wires for carrying a differential signal and being wired in parallel to one another and being connected between the wiring relay submount and the amplifier; an output pin; and another wire, the another wire being connected between the output pin and the wiring relay submount.Type: GrantFiled: March 13, 2007Date of Patent: January 20, 2015Assignee: Hitachi Metals, Ltd.Inventors: Kenichi Tamura, Masahiko Kobayashi
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Publication number: 20150016828Abstract: A burst-mode Rx is provided that has a wide dynamic range, low pulse-width distortion and low technological overhead. The Rx is capable of processing signals having levels that range from low noise levels up to high noise levels. In addition, the Rx is capable of quickly and simultaneously adapting the TIA gain and the bit decision threshold level, thereby eliminating the need to transmit and receive a training bit sequence prior to transmitting and receiving actual data. By simultaneously adapting the TIA gain and the bit decision threshold level on the first bit of actual data received in the Rx, the Rx is capable of being used with short packets and with packets of varying lengths transmitted from different types of transmitters located in the same network.Type: ApplicationFiled: August 29, 2013Publication date: January 15, 2015Applicant: Avago Technologies General IP (Singapore) Pte. LtdInventor: Robert Swoboda