公开(公告)号：US11476635B2

公开(公告)日：2022-10-18

申请号：US16640242

申请日：2018-08-24

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Takayuki Mizuno ,  Akira Isoda ,  Kohki Shibahara ,  Mitsunori Fukutoku ,  Yutaka Miyamoto

IPC分类号： H01S3/23 ,  H01S3/067 ,  H01S3/094 ,  H01S3/0941 ,  H01S3/30 ,  H04B10/297 ,  H01S3/16

摘要： An optically amplified repeater system includes optical transmission paths, a multi-channel optical amplifier, one or more Raman amplification pumping light sources, and a wavelength multiplexer. The multi-channel optical amplifier includes K simultaneous pumping light sources, N optical amplification media, and one or more optical couplers, and simultaneously amplifies, with the K simultaneous pumping light sources, light intensities of optical signals that pass through the N optical amplification media and propagate through the optical transmission paths. Light intensities of the wavelength band of the optical signals is Raman amplified by the Raman amplification pumping light. A light intensity of the Raman amplification pumping light output from the one or more Raman amplification pumping light sources is determined in accordance with characteristic differences between the optical signals passing through the optical transmission paths.

公开(公告)号：US09762982B2

公开(公告)日：2017-09-12

申请号：US15080282

申请日：2016-03-24

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Kazushige Yonenaga ,  Hidehiko Takara ,  Masahiko Jinno ,  Kohki Shibahara ,  Takashi Goh

IPC分类号： H04Q11/00 ,  H04B10/40 ,  H04J14/02 ,  H04B10/516 ,  H04B10/572 ,  H04B10/50 ,  H04L27/26

CPC分类号： H04Q11/0003 ,  H04B10/40 ,  H04B10/506 ,  H04B10/516 ,  H04B10/572 ,  H04J14/02 ,  H04J14/0204 ,  H04J14/0205 ,  H04J14/021 ,  H04J14/0212 ,  H04J14/0224 ,  H04J14/026 ,  H04L27/2697 ,  H04Q11/0005 ,  H04Q2011/0035

摘要： There is provided a multi-flow optical transceiver that includes (a) a plurality of wavelength-tunable light sources, (b) a plurality of optical modulation units which modulates light with an input signal, (c) an optical multiplexing/demultiplexing switch which couples light from at least one of the wavelength-tunable light sources to at least one of the optical modulation units with any power, (d) an optical coupling unit which couples a plurality of lights, modulated by a plurality of the optical modulation units, to at least one waveguide, (e) at least one multiple carrier generating unit which generates multiple carries, arranged at equal frequency intervals, from light of the wavelength-tunable light source, and (f) a wavelength separation unit which branches the multiple carriers from the multiple carrier generating unit for each wavelength.

公开(公告)号：US10985846B2

公开(公告)日：2021-04-20

申请号：US16492917

申请日：2018-03-08

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Kohki Shibahara ,  Takayuki Mizuno ,  Akira Isoda ,  Yutaka Miyamoto

IPC分类号： H04B10/69 ,  H04B1/10 ,  H04B10/2581 ,  H04J14/04 ,  H04J14/06

摘要： A signal receiving apparatus includes at least one signal separating apparatus that separates a specific signal from a plurality of received signals. Each of the at least one signal separating apparatus includes a spatial filtering unit that separates at least one equalized signal and a decision signal outputting unit that generates a first decision signal by deciding the equalized signal and outputs the generated first decision signal. The spatial filtering unit separates the at least one equalized signal by multiplying at least the plurality of received signals among the plurality of received signals and either the first decision signal output from the decision signal outputting unit or a second decision signal output from another signal separating apparatus by predetermined weighting coefficients.

公开(公告)号：US11552714B2

公开(公告)日：2023-01-10

申请号：US17197754

申请日：2021-03-10

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Kohki Shibahara ,  Takayuki Mizuno ,  Akira Isoda ,  Yutaka Miyamoto

IPC分类号： H04B10/69 ,  H04B1/10 ,  H04B10/2581 ,  H04J14/04 ,  H04J14/06

摘要： A signal receiving apparatus includes at least one signal separating apparatus that separates a specific signal from a plurality of received signals. Each of the at least one signal separating apparatus includes a spatial filtering unit that separates at least one equalized signal and a decision signal outputting unit that generates a first decision signal by deciding the equalized signal and outputs the generated first decision signal. The spatial filtering unit separates the at least one equalized signal by multiplying at least the plurality of received signals among the plurality of received signals and either the first decision signal output from the decision signal outputting unit or a second decision signal output from another signal separating apparatus by predetermined weighting coefficients.

公开(公告)号：US10536238B2

公开(公告)日：2020-01-14

申请号：US15775265

申请日：2017-01-11

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Kohki Shibahara ,  Takayuki Mizuno ,  Hiroto Kawakami ,  Yutaka Miyamoto

IPC分类号： H04B10/50 ,  H04J14/04 ,  H04B7/0413 ,  H04B10/69 ,  H04L25/03 ,  H04B7/06 ,  H04L1/06 ,  H04B10/2581

摘要： An optical transmission system includes an optical transmission apparatus and an optical reception apparatus. The optical transmission apparatus includes a conversion unit that converts multiple binary data sequences into data in a predetermined signal format; a coding unit that generates multiple pieces of coded data by performing predetermined coding on each of the multiple pieces of converted data; an optical signal generation unit that generates multiple optical signals by converting the multiple pieces of coded data into optical signals; and a mode multiplexer that converts the multiple optical signals into different modes, generates a mode-division multiplexed optical signal by mode-division multiplexing the optical signals, and transmits the generated mode-division multiplexed optical signal to the optical reception apparatus. The optical reception apparatus includes a mode demultiplexer that demultiplexes the mode-division multiplexed optical signal transmitted from the optical transmission apparatus into light in different modes; a photoelectric conversion unit that converts the light in the multiple different modes into electrical signals; an analog/digital conversion unit that converts the multiple electrical signals into coded data; and an MIMO equalization processing unit that performs MIMO equalization processing on the converted coded data.

公开(公告)号：US09667350B2

公开(公告)日：2017-05-30

申请号：US14758941

申请日：2014-01-24

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Kengo Horikoshi ,  Kohki Shibahara ,  Etsushi Yamazaki ,  Mitsuteru Yoshida ,  Koichi Ishihara ,  Takayuki Kobayashi ,  Yoshiaki Kisaka ,  Takuya Ohara ,  Masahito Tomizawa ,  Tomoyoshi Kataoka

IPC分类号： H04B10/60 ,  H04B10/61 ,  H04L27/06 ,  H04L27/38 ,  H04L7/00

CPC分类号： H04B10/6165 ,  H04L7/0041 ,  H04L7/0075 ,  H04L27/066 ,  H04L27/389

摘要： The optical receiving device with phase compensation apparatus uses coherent opto-electric conversion and is designed for receiving phase- or quadrature-amplitude-modulated optical signals. The phase compensation apparatus includes following elements: a carrier-phase estimation unit that estimates carrier phase errors in a received symbol string; a gain adjustment unit that adjusts weighting of each symbols in phase error evaluation performed in the carrier-phase adjustment unit; a phase-cycle-slip reduction unit with a phase-cycle-slip detector using statistical processing performed on the output symbols from the carrier-phase estimation unit; and a phase compensation circuit that compensates carrier phase errors of the received signal using an output from the carrier phase estimation unit.