利索-全球专利检索

  1. 登录
  2. 注册

搜索结果

50 条记录 (耗时 0.024 秒)

    Receiver for coherent optical communication
    3.
    发明授权
    Receiver for coherent optical communication 失效
    接收器进行相干光通信

    公开(公告)号：US5115332A

    公开(公告)日：1992-05-19

    申请号：US553744

    申请日：1990-07-18

    申请人： Takao Naito ,  Terumi Chikama ,  Shigeki Watanabe ,  Tetsuya Kiyonaga ,  Yoshihito Onoda ,  Hideo Kuwahara

    发明人： Takao Naito ,  Terumi Chikama ,  Shigeki Watanabe ,  Tetsuya Kiyonaga ,  Yoshihito Onoda ,  Hideo Kuwahara

    IPC分类号： H04B10/2513 ,  H04B10/61 ,  H04B10/63 ,  H04B10/64

    CPC分类号： H04B10/61 ,  H04B10/2513 ,  H04B10/613 ,  H04B10/63 ,  H04B10/64

    摘要： A receiver for coherent optical communication in a phase diversity system. An optical hybrid circuit receives a signal beam and receives a local-oscillator beam which has a predetermined phase shift. The optical hybrid circuit branches each beam into pairs, each pair having one signal beam and one local-oscillator beam. These beam pairs are output to first and second photodetectors which each apply a photoelectric conversion, thus producing first and second output signals. The output signals are output to an electrical 90.degree. hybrid circuit which shifts the first signal by 90.degree. and adds it to the second signal to produce a first output signal, and shifts the second signal by 90.degree. and adds it to the first signal to produce a second output signal. The first and second output signals are applied to first and second demodulators, respectively, which delay the signals by a delay corresponding to their frequency. The demodulators output the delayed signals to an adder which adds the two signals to produce an output signal. As a result, the receiver is capable of compensating the wavelength dispension is an optical fiber to secure an enhanced receiving sensitivity.

    Heterodyne receiver for coherent optical communication
    4.
    发明授权
    Heterodyne receiver for coherent optical communication 失效
    用于相干光通信的外差接收机

    公开(公告)号：US5052051A

    公开(公告)日：1991-09-24

    申请号：US424732

    申请日：1989-10-20

    申请人： Takao Naito ,  Terumi Chikama ,  Shigeki Watanabe ,  Tetsuya Kiyonaga ,  Yoshihito Onoda

    发明人： Takao Naito ,  Terumi Chikama ,  Shigeki Watanabe ,  Tetsuya Kiyonaga ,  Yoshihito Onoda

    IPC分类号： G02F2/00 ,  H04B10/07 ,  H04B10/516 ,  H04B10/61

    CPC分类号： H04B10/61 ,  H04B10/614 ,  H04B10/64

    摘要： After mixing the signal light and the local oscillation light with a mixing circuit, two intersecting polarization components are divided by a polarization splitter and respective components are subjected to heterodyne detection by optical receivers. Thereafter, in an electric signal stage, the intermediate frequency signal outputted from the optical receivers are applied to a 90-degree hybrid coupler and the output signal from one of the output ports is demodulated by a demodulator. On the other hand, an intermediate frequency signal outputted from the optical receivers are subjected to a subtraction to provide a principal axis angle monitor signal for the signal light. The signal outputted from the output port from the 90-degree hybrid coupler is used to monitor the elliptic ratio of the signal light and these monitor signals are applied to the polarization control circuit. The polarization control circuit drives the polarization operation apparatus based on said monitor signal to control the polarization state (i.e. a principal axis angle and the elliptic ratio) of the signal light to achieve the optimum state.

    Dual balanced optical signal receiver
    7.
    发明授权
    Dual balanced optical signal receiver 失效
    双平衡光信号接收机

    公开(公告)号：US5003626A

    公开(公告)日：1991-03-26

    申请号：US433431

    申请日：1989-11-08

    申请人： Hideo Kuwahara ,  Terumi Chikama ,  Tetsuya Kiyonaga ,  Chiaki Ohsawa

    发明人： Hideo Kuwahara ,  Terumi Chikama ,  Tetsuya Kiyonaga ,  Chiaki Ohsawa

    IPC分类号： H04B10/61 ,  H04B10/63 ,  H04B10/64

    CPC分类号： H04B10/61 ,  H04B10/614 ,  H04B10/63 ,  H04B10/64

    摘要： An optical signal receiver comprising an optical mixing/polarization splitting unit for producing IF optical signals having two orthogonally polarized components, an optical signal receiving unit for producing four corresponding IF electric signals, and a combining circuit for combining two IF electric signals having one polarization with the other two IF electric signals having the other polarization, suppressing fluctuation of the polarization and the intensity noise of the related local optical signal. The intensity noise suppression is also effective for IF electric signals having a higher frequency range.

    摘要翻译： 一种光信号接收机，包括用于产生具有两个正交极化分量的IF光信号的光混合/偏振分离单元，用于产生四个对应的IF电信号的光信号接收单元，以及组合电路，用于将具有一个极化的两个IF电信号 另外两个具有另一极化的IF电信号抑制偏振波动和相关局部光信号的强度噪声。 强度噪声抑制对于具有较高频率范围的IF电信号也是有效的。

    Bidirectional optical amplifier circuit
    8.
    发明授权
    Bidirectional optical amplifier circuit 失效
    双向光放大器电路

    公开(公告)号：US5875054A

    公开(公告)日：1999-02-23

    申请号：US690794

    申请日：1996-08-01

    申请人： Yoshihito Onoda ,  Terumi Chikama

    发明人： Yoshihito Onoda ,  Terumi Chikama

    IPC分类号： H01S3/07 ,  H01S3/06 ,  H01S3/067 ,  H01S3/094 ,  H01S3/0941 ,  H01S3/10 ,  H01S3/17 ,  H04B10/00 ,  H04B10/079 ,  H04B10/293 ,  H04B10/297 ,  H04B10/40 ,  H04B10/50 ,  H04B10/60 ,  G02F1/35 ,  H01S3/131 ,  H04B10/12

    CPC分类号： H04B10/2972

    摘要： Disclosed is a bidirectional optical amplifier circuit having a function that achieves reliable detection of reflections from an exposed end at low cost. Received optical power is detected; if the detected power is less than a prescribed discrimination level, it is then decided that the detected light is not received signal light but transmitted signal light sent in the direction opposite from it and reflected at an exposed fiber end, and the bias current for a laser diode in the opposite path is reduced to lower the optical output level of an EDF.

    摘要翻译： 公开了一种双向光放大器电路，其具有以低成本可靠地检测来自暴露端的反射的功能。 检测到接收到的光功率; 如果检测到的功率小于规定的识别电平，则判定所检测的光未被接收到信号光，而是在与其相反的方向上发射并在曝光的光纤端反射的发射信号光， 相反路径上的激光二极管减少以降低EDF的光输出电平。

    Optical sending apparatus and channel extension method
    9.
    发明授权
    Optical sending apparatus and channel extension method 失效
    光发送装置和信道扩展方法

    公开(公告)号：US06738181B1

    公开(公告)日：2004-05-18

    申请号：US09650856

    申请日：2000-08-29

    申请人： Hiroshi Nakamoto ,  Takao Naito ,  Terumi Chikama

    发明人： Hiroshi Nakamoto ,  Takao Naito ,  Terumi Chikama

    IPC分类号： H04B1012

    CPC分类号： H04B10/2525 ,  G02B6/2713 ,  G02B6/276 ,  G02B6/29376 ,  H04B10/506 ,  H04B2210/254

    摘要： An optical sending apparatus of this invention includes a plurality of optical signal generating sections, a dispersion compensating section and a wavelength multiplexing section. The dispersion compensating section performs compensation with a predetermined chromatic dispersion value to at least one of polarized light generated by the optical signal generating sections while a predetermined state of polarized light is maintained. The wavelength multiplexing section combines output light outputted from the optical signal generating section with output light passing through the dispersion compensating section so that the polarized light of adjacent wavelengths crosses orthogonal to each other. The optical sending apparatus having such a construction can generate high-density WDM optical signals, the dispersion of which is compensated in advance, by a polarization crossing method.

    摘要翻译： 本发明的光发送装置包括多个光信号产生部分，色散补偿部分和波长复用部分。 色散补偿部在保持预定的偏振光状态的同时，对由光信号产生部产生的偏振光中的至少一个进行预定的色散值的补偿。 波长复用部将从光信号生成部输出的输出光与通过色散补偿部的输出光组合，使得相邻波长的偏振光彼此正交交叉。 具有这种结构的光发送装置可以通过偏振交叉方法产生高分散的WDM光信号，其偏差被预先补偿。