Patents Assigned to NTT Electronics Corporation
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Patent number: 10367100Abstract: A semiconductor element capable of adjusting a barrier height ?Bn and performing zero-bias operation and impedance matching with an antenna for improving detection sensitivity of high-frequency RF electric signals, a method of manufacturing the same, and a semiconductor device having the same. In the semiconductor element, a concentration of InGaAs (n-type InGaAs layer) is intentionally set to be high over a range for preventing the “change of the barrier height caused by the bias” described above up to a deep degeneration range. An electron Fermi level (EF) increases from a band edge of InGaAs (n-type InGaAs layer) to a band edge of InP (InP depletion layer).Type: GrantFiled: August 13, 2015Date of Patent: July 30, 2019Assignee: NTT ELECTRONICS CORPORATIONInventors: Makoto Shimizu, Hiroki Itoh, Tadao Ishibashi, Isamu Kotaka
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Patent number: 10333834Abstract: A packet receiving unit (4) receives an IP packet having a network parameter and a transmission source identifier. A transmission source identifier table (5) records the transmission source identifier of the received IP packet. A packet storage processing unit (6) stores the received IP packet in a first buffer (7) regardless of the network parameter if the transmission source identifier of the received IP packet coincides with a transmission source identifier recorded in the transmission source identifier table. A packet extraction/transmission unit (8) extracts the IP packet stored in the first buffer (7) from the first buffer (7) and transmits the packet.Type: GrantFiled: November 26, 2014Date of Patent: June 25, 2019Assignee: NTT Electronics CorporationInventors: Hiromi Fujita, Hidenori Nagayama
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Patent number: 10310159Abstract: In the case of implementing a polarization separation circuit, a polarization rotator, and the like by inserting a thin-film element into a substrate in one optical interference circuit, one common large-sized groove shared among a plurality of thin-film elements for their insertion has been formed. The optical waveguide type device of the present invention is configured such that at least one groove intersects only one corresponding optical waveguide for inserting the thin-film element and does not intersect other optical waveguides adjacent to the one corresponding optical waveguide. This groove substantially has a rectangular shape, and has a minimum size adapted to the thin-film element to be inserted so as to stably hold and fix the thin-film element in the groove. Adjacent grooves are formed so as to be arranged such that their portions in a direction substantially vertical to the optical waveguide are facing each other.Type: GrantFiled: June 1, 2016Date of Patent: June 4, 2019Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone CorporationInventors: Shigeo Nagashima, Yoshiteru Jinnouchi, Takashi Nakayama, Hiroki Kawashiri, Ikuo Ogawa, Yusuke Nasu, Shunichi Soma
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Patent number: 10305675Abstract: An FIR filter convolutes sampled data obtained by sampling a reception signal with tap coefficients. A phase difference detector detects a phase difference between a synchronization timing of a signal waveform estimated from an output signal of the FIR filter and a sampling timing of the output signal. A tap coefficient adjuster adjusts the tap coefficients so as to reduce the phase difference detected by the phase difference detector and causes the sampling timing of the output signal of the FIR filter to track the synchronization timing.Type: GrantFiled: January 16, 2017Date of Patent: May 28, 2019Assignees: NTT ELECTRONICS CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Yasuharu Onuma, Masahiro Tachibana, Etsushi Yamazaki, Kazuhito Takei, Yuki Yoshida, Masayuki Ikeda, Yoshiaki Kisaka, Masahito Tomizawa
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Publication number: 20190013876Abstract: A coherent optical reception device includes a local oscillation laser that supplies laser light, a coherent optical reception front-end unit that receives a multi-level modulated optical signal, demodulates the optical signal on the basis of the laser light, and converts a demodulated optical signal into an electrical analog signal, an analog-to-digital converter that converts the analog signal into a digital signal, a compensation unit that compensates for an influence of dispersion due to a wavelength or a polarized wave of the optical signal and recovers a carrier phase of the digital signal, a constellation distortion compensation unit that compensates for constellation distortion of the multi-level modulation included in the digital signal in which an influence of dispersion is compensated for by the compensation unit, and an error correction decoding unit that performs error correction of the digital signal in which the constellation distortion is compensated for.Type: ApplicationFiled: October 17, 2016Publication date: January 10, 2019Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT Electronics CorporationInventors: Kengo HORIKOSHI, Mitsuteru YOSHIDA, Seiji OKAMOTO, Eiichi HOSOYA, Etsushi YAMAZAKI, Yasuharu ONUMA, Tomohiro TAKAMUKU, Naoki MIURA, Sadayuki YASUDA
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Patent number: 10126502Abstract: In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding and a core are removed to form a groove on an optical waveguide. The groove is filled with a material (light blocking material) that attenuates the intensity of light. Thus, light input to the termination structure is attenuated by the light blocking material, suppressing crosstalk which possibly effects on other optical devices. Thus, such a termination structure can restrain crosstalk occurred in optical devices integrated in the same substrate and can also suppress crosstalk which possibly effects on any other optical device connected directly to the substrate.Type: GrantFiled: January 26, 2017Date of Patent: November 13, 2018Assignees: NTT ELECTRONICS CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Takanori Ishikawa, Tomoyo Shibazaki, Mitsuru Nagano, Masahiro Yanagisawa, Hiroshi Terui, Mikitaka Itoh
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Patent number: 10128818Abstract: A parallel transfer rate converter inputs first parallel data with number of samples being S1 pieces in synchronism with a first clock, and outputs second parallel data with number of samples being S2=S1×(m/p) pieces (p is an integer equal to or larger than 1) in synchronism with a second clock having a frequency which is p/m times of a frequency of the first clock. A convolution operation device inputs the second parallel data in synchronism with the second clock, generates third parallel data with number of samples being S3=S2×(n/m) pieces (S3 is an integer equal to or larger than 1) by executing a convolution operation with a coefficient indicating a transmission characteristic to the second parallel data, and outputs the third parallel data in synchronism with the second clock.Type: GrantFiled: January 16, 2017Date of Patent: November 13, 2018Assignees: NTT ELECTRONICS CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Yasuharu Onuma, Etsushi Yamazaki, Kazuhito Takei, Osamu Ishida, Kengo Horikoshi, Mitsuteru Yoshida, Yoshiaki Kisaka, Masahito Tomizawa
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Patent number: 10122465Abstract: Signal processing sections selectively switch modulation/demodulation in low-efficiency modulation system and modulation/demodulation in high-efficiency modulation system, and perform digital signal processing. Parallel-side interfaces of input/output interface sections are electrically connected to the signal processing section. A serial-side interface of the input/output interface section is electrically connected to a serial-side interface of the input/output interface section. A selection section electrically connects a parallel-side interface of the input/output interface section to the signal processing section when the low-efficiency modulation system is selected, and electrically connects the parallel-side interface of the input/output interface section to a parallel-side interface of the input/output interface section when the high-efficiency modulation system is selected.Type: GrantFiled: September 5, 2016Date of Patent: November 6, 2018Assignees: NTT ELECTRONICS CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Osamu Ishida, Etsushi Yamazaki, Kazuhito Takei, Masahito Tomizawa, Hideki Nishizawa
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Patent number: 10090921Abstract: A light modulation device detects a power of the modulated optical signal modulated by each of an I-component optical modulator and a Q-component optical modulator, synchronously-detects a component of a frequency fd from the power of the modulated optical signal, outputs a dither signal of a frequency fd/n (where n is a positive integer equal to or larger than 1) applied to a first bias voltage or a second bias voltage when adjusting the first bias voltage or the second bias voltage, outputs two dither signals having a frequency fd/m (where m is a positive integer equal to or larger than 1, where n<m), which are mutually orthogonal to each other, applied to the first and second bias voltages when adjusting a third bias voltage, and adjusting bias voltages by increasing or decreasing bias voltages based on a synchronous detection result.Type: GrantFiled: April 10, 2015Date of Patent: October 2, 2018Assignees: Nippon Telegraph And Telephone Corporation, NTT Electronics CorporationInventors: Mikio Yoneyama, Hiroto Kawakami, Takashi Ono, Akihiko Matsuura, Tomoyoshi Kataoka, Katsuya Tanaka, Masahiro Tachibana, Yuya Oyama
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Patent number: 10054738Abstract: A technique that does not increase the circuit size, does not make the circuit design and manufacturing difficult, and can reduce insertion loss when light enters from a slab waveguide toward an arrayed waveguide or when the light enters from the arrayed waveguide toward the slab waveguide. An optical waveguide provided with a slab waveguide in which a grating is formed therein at a distance from an end, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position where a constructive interference portion of a self-image of the grating is formed.Type: GrantFiled: February 22, 2017Date of Patent: August 21, 2018Assignee: NTT ELECTRONICS CORPORATIONInventors: Keiichi Morita, Kazumi Shimizu, Kouji Kawashima, Tomoharu Niitsu
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Patent number: 10039187Abstract: A flexible substrate having a branch structure in the related art has problems in that: adhesive strength after two bodies are folded and fixed at a bonding region decreases due to an unfolding and opening force at a curve portion and ends of the bonded portions are peeled off and generate gaps; and in a soldering process of the two bodies, the electrodes of one body soldered first are displaced due to reheating in soldering the other body secondly and deteriorate in soldered connection. The present invention provides a new flexible substrate having a branch structure, including first and second bodies joined together, and having a structure in which one of the bodies can be folded back in a longitudinal direction of the whole flexible substrate. Tip ends of the two bodies are provided with multiple electrodes, and are connected by soldering to approximately corresponding positions on both surfaces of an end portion of a printed substrate concerned.Type: GrantFiled: March 17, 2016Date of Patent: July 31, 2018Assignee: NTT ELECTRONICS CORPORATIONInventors: Kazumasa Yoshida, Toshiyuki Ozawa, Teruaki Sato, Atsushi Tomita, Yosuke Takeuchi, Shinji Mino, Yusuke Nasu
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Patent number: 10034011Abstract: A video coding apparatus comprises a motion prediction unit configured to perform motion prediction for a plurality of coding unit sizes of an original image serving as the picture of an input video signal and evaluate results obtained by the motion prediction for the coding unit sizes so as to supply a first evaluation value; a merge mode evaluation unit configured to evaluate each of merge candidates on a coding unit of the merge size determined by a merge size determination unit so as to supply a second evaluation value of each of the merge candidates; and an inter-prediction mode determination unit configured to determine a mode used for coding on the basis of the second evaluation value obtained by the merge mode evaluation unit and the first evaluation value of the coding unit sizes.Type: GrantFiled: August 29, 2016Date of Patent: July 24, 2018Assignees: Nippon Telegraph And Telephone Corporation, NTT Electronics CorporationInventors: Takashi Sano, Takayuki Onishi, Atsushi Shimizu, Katsuyuki Ozaki, Ken Nakamura
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Patent number: 10015508Abstract: Before completion of merge encoding processing of an immediately preceding PU, a controller determines the order of evaluation of merge candidates with the immediately preceding PU excluded from the merge candidates to be evaluated, and a merge-candidate derivation part evaluates each merge candidate in the order of evaluation. After the completion of the merge encoding processing of the immediately preceding PU, the controller re-determines the order of evaluation of merge candidates with the immediately preceding PU included in the merge candidates to be evaluated, and the merge-candidate derivation part evaluates each merge candidate in the re-determined order of evaluation excluding the merge candidate whose evaluation has already been started.Type: GrantFiled: October 25, 2016Date of Patent: July 3, 2018Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone CorporationInventors: Takeshi Yoshizawa, Katsuyuki Ozaki, Takayuki Onishi, Ken Nakamura
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Patent number: 9998405Abstract: A reception buffer of a packet reception apparatus includes a plurality of storage addresses. A packet determination unit receives a packet from a plurality of lines including a main system and an auxiliary system. The packet determination unit obtains a storage address corresponding to a unique number assigned to the packet, and overwrites and stores data of the packet onto the storage address. A packet extraction/transmission unit extracts and transmits the data stored in the reception buffer.Type: GrantFiled: November 25, 2014Date of Patent: June 12, 2018Assignee: NTT ELECTRONICS CORPORATIONInventors: Hidenori Nagayama, Hiromi Fujita, Hidetoshi Suzuki
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Patent number: 9857217Abstract: An opto-electronic integrated circuit includes an optical splitter (12, 13A, 13B) formed on a substrate, the optical splitter branching an input optical signal into N (N is an integer of 2 or more) optical signals, and outputting the optical signals, and N optical phase modulators (15A-15D) formed on the substrate for the respective optical signals output from the optical splitter, the optical phase modulators adjusting the phases of the optical signals based on a phase modulation characteristic in which the phase change amount changes depending on the wavelength of light, and output the optical signals.Type: GrantFiled: September 21, 2012Date of Patent: January 2, 2018Assignees: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT ELECTRONICS CORPORATIONInventors: Atsushi Wakatsuki, Tadao Ishibashi
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Patent number: 9853618Abstract: A transimpedance amplifier circuit (1) includes an amplifier (22) that amplifies a received signal, an automatic gain control (AGC) circuit (2) that controls the amplification gain of the amplifier by a first time constant in accordance with the level of the received signal, and a first selection circuit (25) that selects the first time constant from a plurality of predetermined values. This can simultaneously implement a short time constant of an AGC function necessary to instantaneously respond to a burst signal and a long time constant of the AGC function necessary to obtain a satisfactory bit error rate (BER) characteristic in a continuous signal by an inexpensive and compact circuit arrangement.Type: GrantFiled: September 26, 2014Date of Patent: December 26, 2017Assignees: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT ELECTRONICS CORPORATIONInventors: Hiroshi Koizumi, Masafumi Nogawa, Masatoshi Tobayashi, Masahiro Endo
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Patent number: 9684129Abstract: In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding and a core are removed to form a groove on an optical waveguide. The groove is filled with a material (light blocking material) that attenuates the intensity of light. Thus, light input to the termination structure is attenuated by the light blocking material, suppressing crosstalk which possibly effects on other optical devices. Thus, such a termination structure can restrain crosstalk occurred in optical devices integrated in the same substrate and can also suppress crosstalk which possibly effects on any other optical device connected directly to the substrate.Type: GrantFiled: March 26, 2015Date of Patent: June 20, 2017Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone CorporationInventors: Takanori Ishikawa, Tomoyo Shibazaki, Mitsuru Nagano, Masahiro Yanagisawa, Hiroshi Terui, Mikitaka Itoh
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Publication number: 20170117961Abstract: A light modulation device detects a power of the modulated optical signal modulated by each of an I-component optical modulator and a Q-component optical modulator, synchronously-detects a component of a frequency fd from the power of the modulated optical signal, outputs a dither signal of a frequency fd/n (where n is a positive integer equal to or larger than 1) applied to a first bias voltage or a second bias voltage when adjusting the first bias voltage or the second bias voltage, outputs two dither signals having a frequency fd/m (where m is a positive integer equal to or larger than 1, where n<m), which are mutually orthogonal to each other, applied to the first and second bias voltages when adjusting a third bias voltage, and adjusting bias voltages by increasing or decreasing bias voltages based on a synchronous detection result.Type: ApplicationFiled: April 10, 2015Publication date: April 27, 2017Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT Electronics CorporationInventors: Mikio YONEYAMA, Hiroto KAWAKAMI, Takashi ONO, Akihiko MATSUURA, Tomoyoshi KATAOKA, Katsuya TANAKA, Masahiro TACHIBANA, Yuya OYAMA
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Patent number: 9618694Abstract: A technique that does not increase the circuit size, does not make the circuit design and manufacturing difficult, and can reduce insertion loss when light enters from a slab waveguide toward an arrayed waveguide or when the light enters from the arrayed waveguide toward the slab waveguide. An optical waveguide provided with a slab waveguide in which a grating is formed therein at a distance from an end, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position where a constructive interference portion of a self-image of the grating is formed.Type: GrantFiled: May 10, 2011Date of Patent: April 11, 2017Assignee: NTT ELECTRONICS CORPORATIONInventors: Keiichi Morita, Kazumi Shimizu, Kouji Kawashima, Tomoharu Niitsu
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Patent number: 9560763Abstract: A package for optical module includes a flat-plate-shaped metal base, and a ceramic circuit board in which a plurality of terminals are arranged in a longitudinal direction, and which is joined to an upper surface of the metal base by soldering. The ceramic circuit board has a shape change portion in which the ceramic circuit board is changed in shape along the longitudinal direction, and a region of the ceramic circuit board not including the shape change portion is joined to the metal base by soldering. The shape change portion of the ceramic circuit board is a portion where a width is changed along the longitudinal direction, or a portion where a thickness is changed along the longitudinal direction.Type: GrantFiled: July 1, 2013Date of Patent: January 31, 2017Assignees: Nippon Telegraph and Telephone Corporation, NTT Electronics corporationInventors: Ikuo Ogawa, Ryoichi Kasahara, Toshiki Nishizawa, Yuji Mitsuhashi