公开(公告)号：US20190312639A1

公开(公告)日：2019-10-10

申请号：US16466702

申请日：2017-12-11

Applicant: NEC Corporation

Inventor： Yoshimasa ONO ,  Toshiharu ITO

IPC: H04B10/079 ,  H04B10/118

Abstract: An optical space communication device includes first and second optical antennas that transmit first and second transmission light and receive first and second reception light, first and second delay circuits that provide a delay to transmission data included in the first and second transmission light, third and fourth delay circuits that provide a delay to reception data included in the first and second reception light, and a receiver that sets a delay of at least one of the first delay circuit and the second delay circuit and sets a delay of at least one of the third delay circuit and the fourth delay circuit, based on delays between the first and third delay circuits and the first optical antenna, delays between the second and fourth delay circuits and a fourth optical antenna, and delays between a communication destination and the third and fourth delay circuits.

公开(公告)号：US20180323904A1

公开(公告)日：2018-11-08

申请号：US15773035

申请日：2016-11-01

Applicant: NEC CORPORATION

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

IPC: H04L1/00 ,  H04L27/22 ,  H04B10/61 ,  H04B10/118 ,  H04L27/00

CPC classification number: H04L1/0057 ,  H04B10/118 ,  H04B10/61 ,  H04L27/0014 ,  H04L27/22 ,  H04L2027/0057

Abstract: An appropriate synthesized signal cannot be obtained by only correcting relative phase errors of a plurality of received signals; therefore, a received signal processor according to an exemplary aspect of the present invention includes a plurality of signal-to-noise ratio estimation means for estimating respective signal-to-noise ratios of a plurality of digital signal sequences in which relative phase errors of a plurality of received signal sequences having been corrected; a plurality of temporary decision means for performing symbol decisions of the plurality of digital signal sequences and outputting symbol signal sequences; symbol-map-rotation determination means for determining respective phase rotation amounts of the plurality of digital signal sequences from the plurality of symbol signal sequences and the respective signal-to-noise ratios of the plurality of digital signal sequences; and a plurality of phase rotation means for rotating phases of the plurality of digital signal sequences respectively based on the phase rotation amounts.