公开(公告)号：US20170207850A1

公开(公告)日：2017-07-20

申请号：US15327862

申请日：2015-07-17

Applicant: NEC Corporation

Inventor： Seigo TAKAHASHI ,  Toshiharu ITO ,  Kohei HOSOKAWA

IPC: H04B10/112 ,  H04B10/60

CPC classification number: H04B10/112 ,  H04B10/60

Abstract: The circuit size of a signal processing circuit increases in a free space optical receiver, which increases in cost, because the signal processing becomes complex attempting to improve the coupling efficiency between received light and a fiber; therefore, a free space optical receiver according to an exemplary aspect of the present invention includes a light collecting means for collecting laser light having propagated through a free space transmission path; a multi-mode transmission medium for receiving input of the laser light and outputting multi-mode light; a multi-mode signal processing means for outputting a plurality of received electrical signals based on part of the multi-mode light; a monitor means for monitoring signal information based on the multi-mode light; a control means for controlling an operation of the multi-mode signal processing means based on the signal information; and a signal processing means for performing signal processing on the plurality of received electrical signals and outputting an output signal synthesized from the plurality of received electrical signals.

公开(公告)号：US20160028480A1

公开(公告)日：2016-01-28

申请号：US14774784

申请日：2014-03-11

Applicant: NEC CORPORATION

Inventor： Toshiharu ITO ,  Emmanuel LE TAILLANDIER DE GABORY

IPC: H04B10/2507 ,  H04B10/556 ,  H04B10/61

CPC classification number: H04B10/2507 ,  H04B10/2581 ,  H04B10/5561 ,  H04B10/61 ,  H04B10/6165 ,  H04J14/04 ,  H04J14/06

Abstract: An optical transmitter (10) outputs basic transmission light of an optical signal for transmission to an optical receiver (20). A first optical signal generation means (210) of the optical receiver (20) receives the optical signal for transmission, and generates a first optical signal by causing the received optical signal for transmission and locally generated light to interfere with each other. A second optical signal generation means (220) of the optical receiver (20) receives the transmission light, and generates an optical signal for denoising by causing the received transmission light and the locally generated light to interfere with each other. A first photoelectric conversion means (230) of the optical receiver (20) photoelectrically converts the first optical signal to generate a received signal. A second photoelectric conversion means (240) photoelectrically converts the optical signal for denoising to generate a noise signal. A denoising means (250) removes a noise component from the received signal using the noise signal.

Abstract translation: 光发射机（10）输出用于传输的光信号的基本传输光到光接收器（20）。 光接收器（20）的第一光信号产生装置（210）接收用于传输的光信号，并且通过使接收到的光信号发送和本地产生的光彼此干扰而产生第一光信号。 光接收器（20）的第二光信号产生装置（220）接收传输光，并通过使接收到的传输光和局部产生的光彼此干扰而产生用于去噪的光信号。 光接收器（20）的第一光电转换装置（230）对第一光信号进行光电转换以产生接收信号。 第二光电转换装置（240）对用于去噪的光信号进行光电转换以产生噪声信号。 去噪装置（250）使用噪声信号从接收信号中去除噪声分量。

公开(公告)号：US20220256398A1

公开(公告)日：2022-08-11

申请号：US17616231

申请日：2020-02-05

Applicant: NEC Corporation

Inventor： Yohei HASEGAWA ,  Toshiharu ITO

IPC: H04W28/04 ,  H04L1/00 ,  H04L1/20

Abstract: A communication system includes: a transmitting-side terminal; a transmitting-side communication apparatus configured to receive data transmitted by the transmitting-side terminal and transmit the received data by radio transmission to a receiving-side communication apparatus; and the receiving-side communication apparatus configured to transmit the data received by radio transmission from the transmitting-side communication apparatus to a receiving-side terminal. The transmitting-side terminal includes a control unit configured to control a transmission speed of the data addressed to the receiving-side terminal based on a first error rate that is an error rate of radio transmission from the transmitting-side communication apparatus to the receiving-side communication apparatus and a second error rate that is an error rate of transmission from the transmitting-side terminal to the receiving-side terminal.

公开(公告)号：US20200044737A1

公开(公告)日：2020-02-06

申请号：US16605321

申请日：2018-04-18

Applicant: NEC Corporation

Inventor： Manabu ARIKAWA ,  Toshiharu ITO

IPC: H04B10/118 ,  H04B10/61 ,  H04B17/336

Abstract: The signal combining device includes: a plurality of first filters to subject each of a plurality of reception signals to processing with first filter coefficients, the plurality of reception signals being generated by subjecting optical signals to coherent detection; a plurality of second filters to subject outputs of the first filters to processing with second filter coefficients; a combiner to output combined signals acquired by combining outputs of the second filters; and a controller to perform adaptive control for each of the first filter coefficients and each of the second filter coefficients with different step sizes in each other, so that the combined signals are in a predetermined state, based on the reception signals input to the first filters and the combined signals, and to switch an update state of a filter coefficient of each of the first filters, based on magnitudes of the second filter coefficients.

公开(公告)号：US20200015099A1

公开(公告)日：2020-01-09

申请号：US16483083

申请日：2018-02-14

Applicant: NEC Corporation

Inventor： Yasunori FUTATSUGI ,  Toshiharu ITO ,  Manabu ARIKAWA

IPC: H04W24/02 ,  H04L12/26 ,  H04L1/08 ,  H04W40/12

Abstract: It is difficult in related communication apparatuses to avoid degradation of communication quality due to fading and achieve sufficient throughput performance; therefore, a communication apparatus according to an exemplary aspect of the present invention includes fade avoidance rate calculation means for calculating, from a time variation in communication quality information and a transmission pattern in transmitting a communication packet repeatedly, a fade avoidance rate of a probability that the communication packet lies outside a fade duration, with respect to each transmission pattern; throughput calculation means for calculating, from the transmission pattern and the fade avoidance rate, a throughput of the communication packet with respect to each transmission pattern; and transmission pattern determination means for determining an optimum transmission pattern, of the transmission pattern, by which the throughput is maximized.

公开(公告)号：US20240195488A1

公开(公告)日：2024-06-13

申请号：US18533257

申请日：2023-12-08

Applicant: NEC Corporation

Inventor： Junichi HIGUCHI ,  Hiroaki MIYOSHI ,  Toshiharu ITO ,  Youichi HIDAKA ,  Takahiro KOISHI ,  Takashi OONUKI

IPC: H04B7/185

CPC classification number: H04B7/18515 ,  H04B7/18513

Abstract: A first satellite includes a first host-side bridge and a first host, connected with a network via the first host-side bridge, mounted thereon. A second satellite includes a first I/O-side bridge and a first I/O device, connected with the network via the first I/O-side bridge, mounted thereon. A management device selects the first host mounted on at least one of the first satellites and the first I/O device mounted on at least one of the second satellites, according to a configuration request, and forms an information processing device in which the first host-side bridge connected with the selected first host and the first I/O-side bridge connected with the selected first I/O device constitute a virtual computer internal bus.

公开(公告)号：US20220224418A1

公开(公告)日：2022-07-14

申请号：US17613149

申请日：2020-05-13

Applicant: NEC Corporation

Inventor： Manabu ARIKAWA ,  Toshiharu ITO

IPC: H04B10/61 ,  H04B10/118

Abstract: A receiving optical system control device according to the present invention has: a light intensity calculation means for calculating, from a reception signal acquired by receiving, for each of plurality of mode light beams which are of the incident optical beams and which have been coupled to a plurality of propagation modes of the optical transmission medium by an optical system provided with a variable mechanism, the light intensity of each of the mode light beams; an optical phase calculation means for calculating the optical phase of each of the mode light beams from the reception signal; a relative phase calculation means for calculating the relative phase between the plurality of mode light beams from the optical phases; and a control amount calculation means for calculating the control amount of the variable mechanism from the light intensity and the relative phase.

公开(公告)号：US20210159976A1

公开(公告)日：2021-05-27

申请号：US17044213

申请日：2019-03-22

Applicant: NEC CORPORATION

Inventor： Manabu ARIKAWA ,  Toshiharu ITO

IPC: H04B10/11 ,  H04J14/06

Abstract: An optical reception terminal includes a plurality of matrix filters (40, 41) respectively provided for a plurality of modes and configured to perform polarization separation and equalization on a coherently received signal in a corresponding mode, and two combining filters (50,51) respectively provided for two polarizations and configured to combine signals in corresponding polarization among signals output from the plurality of matrix filters (40, 41) after weighting the signals. Filter coefficients of the plurality of matrix filters (40, 41) and weighting coefficients of the two combining filters (50,51) are controlled based on a deviation from a desired state of both signals in two polarizations after combining by the two combining filters (50,51), so as to minimize a sum of deviations.

公开(公告)号：US20170264365A1

公开(公告)日：2017-09-14

申请号：US15529145

申请日：2015-11-18

Applicant: NEC Corporation

Inventor： Seigo TAKAHASHI ,  Toshiharu ITO ,  Akihiro TANAKA ,  Kohei HOSOKAWA ,  Manabu ARIKAWA

IPC: H04B10/118 ,  H04B10/548 ,  H04B10/112 ,  H04B10/2581 ,  H04B10/67

CPC classification number: H04B10/118 ,  H04B10/112 ,  H04B10/2581 ,  H04B10/548 ,  H04B10/676

Abstract: It is difficult in a free space optical receiver to satisfy both of the stable receiving and the highly sensitive receiving; therefore, a free space optical receiver according to an exemplary aspect of the present invention includes a light collecting means for collecting laser light having propagated through a free space transmission path; a multimode light generating means for receiving input of the laser light collected by the light collecting means, exciting multimode light, and outputting multimode propagation light including a plurality of propagation mode light beams with a number smaller than a number of multimode light beams possible to be excited; and a mode separating means for separating the multimode propagation light into the plurality of propagation mode light beams and outputting the plurality of propagation mode light beams.

公开(公告)号：US20200304213A1

公开(公告)日：2020-09-24

申请号：US16088328

申请日：2017-03-17

Applicant: NEC Corporation

Inventor： Kohei HOSOKAWA ,  Toshiharu ITO ,  Seigo TAKAHASHI ,  Manabu ARIKAWA ,  Takashi ISHIKAWA ,  Yoshimasa ONO

IPC: H04B10/69 ,  H04B10/11 ,  H04B17/336

Abstract: The objective of the present invention is to reduce the size of a receiving device circuit in an optical space communication system while maintaining communication stability. A data receiving device which decodes one item of data from a plurality of input signals includes: two or more digital signal processing means for subjecting the plurality of input signals to signal processing; a first recording means for temporarily recording the plurality of input signals; a SN ratio estimating means for estimating S/N ratios of each of the plurality of input signals and determining the number of the plurality of input signals to be combined, and the signals to be combined; and a scheduling means for carrying out overall control on the basis of the results from the SN ratio estimating means.