公开(公告)号：US20170070289A1

公开(公告)日：2017-03-09

申请号：US15123103

申请日：2014-03-13

Applicant: NEC Corporation

Inventor： Seigo TAKAHASHI ,  Toshiharu ITO ,  Kohei HOSOKAWA

IPC: H04B10/112 ,  H04B10/60

CPC classification number: H04B10/1121 ,  H04B10/60 ,  H04J14/02

Abstract: It is impossible to prevent the deterioration of the coupling efficiency between received light and a single mode fiber, and difficult to achieve a higher transmission rate, with respect to a free space optical communication receiver; therefore, a free space optical receiver according to an exemplary aspect of the present invention includes light collecting means for collecting laser light having propagated through a free space transmission path; mode controlling means for separating the laser light collected by the light collecting means into a plurality of propagation mode beams depending on a wave-front fluctuation of the laser light and outputting the propagation mode beams; a plurality of single mode transmission media for guiding the plurality of propagation mode beams, respectively; and a plurality of light receiving means for receiving the plurality of propagation mode beams respectively through the plurality of single mode transmission media.

Abstract translation: 相对于自由空间光通信接收机，不可能防止接收光和单模光纤之间的耦合效率的劣化，难以实现更高的传输速率; 因此，根据本发明的示例性方面的自由空间光学接收器包括：聚光装置，用于收集通过自由空间传播路径传播的激光; 模式控制装置，用于根据激光的波前波动将由光收集装置收集的激光分离成多个传播模式光束，并输出传播模式光束; 分别引导多个传播模式波束的多个单模传输介质; 以及多个光接收装置，用于分别通过多个单模传输介质接收多个传播模式光束。

公开(公告)号：US20150311983A1

公开(公告)日：2015-10-29

申请号：US14651037

申请日：2013-12-11

Applicant: NEC CORPORATION

Inventor： Kohei HOSOKAWA ,  Yuichi NAKAMURA

IPC: H04B10/61

CPC classification number: H04B10/6164

Abstract: A frequency offset compensation apparatus includes: first FFT means for performing a discrete-time Fourier transform of an input signal; second FFT means for performing a discrete-time Fourier transform; and offset compensation means for changing an order of output data of the first FFT means according to a frequency offset compensation amount, and rearranging the output data, and then inputting the output data to the second FFT means. This makes possible a frequency offset compensation without needing a new complex multiplier or a new memory in optical communication.

Abstract translation: 频偏补偿装置包括：第一FFT装置，用于执行输入信号的离散时间傅里叶变换; 用于执行离散时间傅里叶变换的第二FFT装置; 以及偏移补偿装置，用于根据频率偏移补偿量改变第一FFT装置的输出数据的顺序，并重新排列输出数据，然后将输出数据输入到第二FFT装置。 这使得可以进行频偏补偿而不需要新的复数乘法器或光通信中的新存储器。