Patents by Inventor Masamichi Fujiwara
Masamichi Fujiwara has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20230065159Abstract: In general, according to an embodiment, a memory system includes a memory device including a memory cell; and a controller. The controller is configured to: receive first data from the memory cell in a first data reading; receive second data from the memory cell in a second data reading that is different from the first data reading; convert a first value that is based on the first data and the second data, to a second value in accordance with a first relationship; and convert the first value to a third value in accordance with a second relationship that is different from the first relationship.Type: ApplicationFiled: November 10, 2022Publication date: March 2, 2023Applicant: Kioxia CorporationInventors: Tsukasa TOKUTOMI, Masanobu SHIRAKAWA, Marie TAKADA, Masamichi FUJIWARA, Kazumasa YAMAMOTO, Naoaki KOKUBUN, Tatsuro HITOMI, Hironori UCHIKAWA
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Patent number: 11595132Abstract: An ADC (12) in an optical receiver (1) generates a sample signal composed of time series samples by oversampling a received signal that is an electrical signal converted from an optical signal by a light receiving unit (11). A symbol timing detection unit (132) of a DSP unit (13) detects a symbol timing in the sample signal. When it is determined that a symbol timing is appearing at a longer interval than a predetermined interval based on this detection result, a symbol timing adjusting unit (133) skips one or more samples included in the sample signal to read out samples at the predetermined interval, while when it is determined that the symbol timing is appearing at a shorter interval than the predetermined interval, the symbol timing adjusting unit inserts the same samples as one or more samples included in the sample signal immediately after the one or more samples to read out the samples at the predetermined interval.Type: GrantFiled: August 27, 2019Date of Patent: February 28, 2023Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Noriko Iiyama, Masamichi Fujiwara, Junichi Kani
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Patent number: 11539437Abstract: A signal processing device included in an optical reception device configured to receive a burst optical signal transmitted by one of a plurality of optical transmission devices, includes a symbol timing detecting unit configured to detect a symbol timing based on sample signals obtained by oversampling the burst optical signal converted into an electric signal with a sampling rate higher than a symbol rate, an adaptive equalization filter unit configured to perform an equalization process on the sample signals, and a timing matching unit configured to match timing such that, when the adaptive equalization filter unit takes in the sample signals, one of the taken-in sample signals corresponding to the symbol timing is given to a tap of which a tap coefficient has a maximum value among taps included in the adaptive equalization filter unit.Type: GrantFiled: June 5, 2019Date of Patent: December 27, 2022Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Noriko Iiyama, Masamichi Fujiwara, Junichi Kani
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Patent number: 11537465Abstract: In general, according to an embodiment, a memory system includes a memory device including a memory cell; and a controller. The controller is configured to: receive first data from the memory cell in a first data reading; receive second data from the memory cell in a second data reading that is different from the first data reading; convert a first value that is based on the first data and the second data, to a second value in accordance with a first relationship; and convert the first value to a third value in accordance with a second relationship that is different from the first relationship.Type: GrantFiled: February 12, 2021Date of Patent: December 27, 2022Assignee: KIOXIA CORPORATIONInventors: Tsukasa Tokutomi, Masanobu Shirakawa, Marie Takada, Masamichi Fujiwara, Kazumasa Yamamoto, Naoaki Kokubun, Tatsuro Hitomi, Hironori Uchikawa
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Publication number: 20220368428Abstract: An optical reception device including: a wavelength selection unit configured to split an optical signal amplified by an optical amplifier into different paths according to wavelengths by using a wavelength multiplexer/demultiplexer, and control a passage state of a passage target optical switch through which the optical signal is to be passed, out of a plurality of optical switches provided on the respective paths, to select an optical signal of a path where the optical signal entered and output the optical signal to a receiver; and a wavelength detection unit configured to detect the wavelength of an optical signal by using each of a plurality of optical detectors, determine the passage target optical switch based on a detection result, and output, to the determined passage target optical switch, a control signal for controlling the passage target optical switch so as to enter the passage state, the optical detectors being respectively provided on different paths that are different from the paths on which tType: ApplicationFiled: July 1, 2019Publication date: November 17, 2022Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Ryo IGARASHI, Takuya KANAI, Masamichi FUJIWARA, Junichi KANI
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Publication number: 20220368427Abstract: An optical reception device including: a local light transmission unit configured to generate a plurality of local lights having different wavelengths, select a local light having a wavelength that is close to the wavelength of a received optical signal from among the plurality of generated local lights having different wavelengths, and transmit the selected local light to a coherent receiver; a demultiplexing unit configured to demultiplex a received optical signal and transmit the demultiplexed optical signal to the coherent receiver via a first path; and a wavelength detection unit configured to input the optical signal demultiplexed by the demultiplexing unit via a second path, split the input optical signal into different paths according to wavelengths by using a wavelength multiplexer/demultiplexer, and output, to the local light transmission unit, a control signal for causing the local light transmission unit to output a local light having a frequency that corresponds to a path in which the optical sigType: ApplicationFiled: July 1, 2019Publication date: November 17, 2022Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Ryo IGARASHI, Takuya KANAI, Masamichi FUJIWARA, Junichi KANI
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Patent number: 11451305Abstract: Upon receipt of a coherent optical signal that includes a training signal generated using a code sequence constituted by multi-value phase modulation symbols, in which a deviation angle of a vector average of a one-symbol delay differential component of a signal generated on the basis of the code sequence has a prescribed angle and a modulation phase difference between adjacent symbols has a fixed, repeated pattern, a reception training signal corresponding to a training code sequence for frequency offset estimation is detected within a reception signal acquired by converting the received coherent optical signal into an electric signal, a plurality of delay differential components are calculated on the basis of the detected reception training signal and at least two delay signals of the reception training signal, each delay signal having a different number of delay symbols, and an averaged frequency offset amount is calculated using the calculated plurality of delay differential components.Type: GrantFiled: August 30, 2019Date of Patent: September 20, 2022Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Ryo Igarashi, Masamichi Fujiwara, Takuya Kanai
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Publication number: 20220239375Abstract: An optical communication system includes a first optical communication device and a second optical communication device that transmit and receive an optical signal via an optical transmission line. The optical transmission line includes: a first section optical transmission line connected to the first optical communication device; and a second section optical transmission line connected to the second optical communication device and having fewer reflection points of the optical signal than the first section optical transmission line.Type: ApplicationFiled: June 11, 2019Publication date: July 28, 2022Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Masamichi FUJIWARA, Ryo lGARASHI, Takuya KANAI
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Publication number: 20220130468Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes first to fourth word lines and first to fourth memory cells. The controller is configured to issue first and second instructions. The controller is further configured to execute a first operation to obtain a first read voltage based on a threshold distribution of the first memory cell, and a second operation to read data from the second memory cell.Type: ApplicationFiled: January 4, 2022Publication date: April 28, 2022Applicant: Kioxia CorporationInventors: Tsukasa TOKUTOMI, Masanobu SHIRAKAWA, Marie TAKADA, Shohei ASAMI, Masamichi FUJIWARA
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Patent number: 11222703Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes first to fourth word lines and first to fourth memory cells. The controller is configured to issue first and second instructions. The controller is further configured to execute a first operation to obtain a first read voltage based on a threshold distribution of the first memory cell, and a second operation to read data from the second memory cell.Type: GrantFiled: December 22, 2020Date of Patent: January 11, 2022Assignee: TOSHIBA MEMORY CORPORATIONInventors: Tsukasa Tokutomi, Masanobu Shirakawa, Marie Takada, Shohei Asami, Masamichi Fujiwara
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Publication number: 20210399809Abstract: Upon receipt of a coherent optical signal that includes a training signal generated using a code sequence constituted by multi-value phase modulation symbols, in which a deviation angle of a vector average of a one-symbol delay differential component of a signal generated on the basis of the code sequence has a prescribed angle and a modulation phase difference between adjacent symbols has a fixed, repeated pattern, a reception training signal corresponding to a training code sequence for frequency offset estimation is detected within a reception signal acquired by converting the received coherent optical signal into an electric signal, a plurality of delay differential components are calculated on the basis of the detected reception training signal and at least two delay signals of the reception training signal, each delay signal having a different number of delay symbols, and an averaged frequency offset amount is calculated using the calculated plurality of delay differential components.Type: ApplicationFiled: August 30, 2019Publication date: December 23, 2021Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Ryo IGARASHI, Masamichi FUJIWARA, Takuya KANAI
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Publication number: 20210336706Abstract: An ADC (12) in an optical receiver (1) generates a sample signal composed of time series samples by oversampling a received signal that is an electrical signal converted from an optical signal by a light receiving unit (11). A symbol timing detection unit (132) of a DSP unit (13) detects a symbol timing in the sample signal. When it is determined that a symbol timing is appearing at a longer interval than a predetermined interval based on this detection result, a symbol timing adjusting unit (133) skips one or more samples included in the sample signal to read out samples at the predetermined interval, while when it is determined that the symbol timing is appearing at a shorter interval than the predetermined interval, the symbol timing adjusting unit inserts the same samples as one or more samples included in the sample signal immediately after the one or more samples to read out the samples at the predetermined interval.Type: ApplicationFiled: August 27, 2019Publication date: October 28, 2021Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Noriko IIYAMA, Masamichi FUJIWARA, Junichi KANI
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Publication number: 20210258075Abstract: A signal processing device included in an optical reception device configured to receive a burst optical signal transmitted by one of a plurality of optical transmission devices, includes a symbol timing detecting unit configured to detect a symbol timing based on sample signals obtained by oversampling the burst optical signal converted into an electric signal with a sampling rate higher than a symbol rate, an adaptive equalization filter unit configured to perform an equalization process on the sample signals, and a timing matching unit configured to match timing such that, when the adaptive equalization filter unit takes in the sample signals, one of the taken-in sample signals corresponding to the symbol timing is given to a tap of which a tap coefficient has a maximum value among taps included in the adaptive equalization filter unit.Type: ApplicationFiled: June 5, 2019Publication date: August 19, 2021Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATIONInventors: Noriko IIYAMA, Masamichi FUJIWARA, Junichi KANI
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Publication number: 20210165713Abstract: In general, according to an embodiment, a memory system includes a memory device including a memory cell; and a controller. The controller is configured to: receive first data from the memory cell in a first data reading; receive second data from the memory cell in a second data reading that is different from the first data reading; convert a first value that is based on the first data and the second data, to a second value in accordance with a first relationship; and convert the first value to a third value in accordance with a second relationship that is different from the first relationship.Type: ApplicationFiled: February 12, 2021Publication date: June 3, 2021Applicant: Toshiba Memory CorporationInventors: Tsukasa TOKUTOMI, Masanobu SHIRAKAWA, Marie TAKADA, Masamichi FUJIWARA, Kazumasa YAMAMOTO, Naoaki KOKUBUN, Tatsuro HITOMI, Hironori UCHIKAWA
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Patent number: 11008084Abstract: A hybrid type vessel propulsion apparatus includes an engine, an electric motor, a propeller shaft that rotates together with a propeller, a first transmission path, a second transmission path, and a third transmission path. The first transmission path transmits power of the engine to the propeller shaft. The second transmission path transmits power of the electric motor to the propeller shaft without transmitting the power through the first transmission path. The third transmission path transmits a portion of the power of the engine, which has been transmitted from the first transmission path to the propeller shaft, to the electric motor in order for the electric motor to generate electricity.Type: GrantFiled: August 8, 2019Date of Patent: May 18, 2021Assignee: YAMAHA HATSUDOKI KABUSHIKI KAISHAInventors: Daisuke Nakamura, Takayoshi Suzuki, Masamichi Fujiwara
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Publication number: 20210110875Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes first to fourth word lines and first to fourth memory cells. The controller is configured to issue first and second instructions. The controller is further configured to execute a first operation to obtain a first read voltage based on a threshold distribution of the first memory cell, and a second operation to read data from the second memory cell.Type: ApplicationFiled: December 22, 2020Publication date: April 15, 2021Applicant: TOSHIBA MEMORY CORPORATIONInventors: Tsukasa TOKUTOMI, Masanobu SHIRAKAWA, Marie TAKADA, Shohei ASAMI, Masamichi FUJIWARA
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Patent number: 10956264Abstract: In general, according to an embodiment, a memory system includes a memory device including a memory cell; and a controller. The controller is configured to: receive first data from the memory cell in a first data reading; receive second data from the memory cell in a second data reading that is different from the first data reading; convert a first value that is based on the first data and the second data, to a second value in accordance with a first relationship; and convert the first value to a third value in accordance with a second relationship that is different from the first relationship.Type: GrantFiled: August 21, 2019Date of Patent: March 23, 2021Assignee: Toshiba Memory CorporationInventors: Tsukasa Tokutomi, Masanobu Shirakawa, Marie Takada, Masamichi Fujiwara, Kazumasa Yamamoto, Naoaki Kokubun, Tatsuro Hitomi, Hironori Uchikawa
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Patent number: 10910067Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes first to fourth word lines and first to fourth memory cells. The controller is configured to issue first and second instructions. The controller is further configured to execute a first operation to obtain a first read voltage based on a threshold distribution of the first memory cell, and a second operation to read data from the second memory cell.Type: GrantFiled: March 11, 2019Date of Patent: February 2, 2021Assignee: TOSHIBA MEMORY CORPORATIONInventors: Tsukasa Tokutomi, Masanobu Shirakawa, Marie Takada, Shohei Asami, Masamichi Fujiwara
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Publication number: 20200075106Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes first to fourth word lines and first to fourth memory cells. The controller is configured to issue first and second instructions. The controller is further configured to execute a first operation to obtain a first read voltage based on a threshold distribution of the first memory cell, and a second operation to read data from the second memory cell.Type: ApplicationFiled: March 11, 2019Publication date: March 5, 2020Applicant: TOSHIBA MEMORY CORPORATIONInventors: Tsukasa TOKUTOMI, Masanobu SHIRAKAWA, Marie TAKADA, Shohei ASAMI, Masamichi FUJIWARA
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Publication number: 20200062362Abstract: A hybrid type vessel propulsion apparatus includes an engine, an electric motor, a propeller shaft that rotates together with a propeller, a first transmission path, a second transmission path, and a third transmission path. The first transmission path transmits power of the engine to the propeller shaft. The second transmission path transmits power of the electric motor to the propeller shaft without transmitting the power through the first transmission path. The third transmission path transmits a portion of the power of the engine, which has been transmitted from the first transmission path to the propeller shaft, to the electric motor in order for the electric motor to generate electricity.Type: ApplicationFiled: August 8, 2019Publication date: February 27, 2020Inventors: Daisuke NAKAMURA, Takayoshi SUZUKI, Masamichi FUJIWARA