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    Mobile communication system
    1.
    发明授权
    Mobile communication system 失效
    移动通信系统

    公开(公告)号：US5400391A

    公开(公告)日：1995-03-21

    申请号：US289545

    申请日：1994-08-11

    申请人： Katsumi Emura ,  Makoto Shibutani ,  Junji Namiki ,  Toshihito Kanai

    发明人： Katsumi Emura ,  Makoto Shibutani ,  Junji Namiki ,  Toshihito Kanai

    IPC分类号： H04B10/2575 ,  H04W88/08 ,  H04M11/00

    CPC分类号： H04B10/25753 ,  H04B10/25752 ,  H04B10/25759 ,  H04W88/085

    摘要： A cellular mobile communication system in which each of one or more cells is provided with a base radio station, and mobile terminals communicate with the base radio stations. Base radio stations (21, 22 and 23) are connected to a central base station (100) by optical fibers. The central base station is connected to a mobile switching center (50). Each of the base radio stations is provided with an O/E converter (201) and E/O converter (207). The O/E converter converts a optical signal containing speech signals and a call connection control signal into RF signals. The E/O converter (207) converts RF signals, received from a mobile terminal (11) via an antenna (204), into optical signals and transmits the optical signals to the central base station. The central base station comprises O/E converters (301-303) for converting optical signals from each base radio station into RF signals; receivers (401-403) for demodulating these RF signals; transmitters (406-408) for converting speech signals and a call connection control signal from the mobile switching center into RF signals; and E/O converters (304-306) for converting these RF signals into optical signals and transmitting the optical signals to a base radio station.

    摘要翻译： 一种蜂窝移动通信系统，其中一个或多个小区中的每一个被提供有基站无线电台，并且移动终端与基站无线电台进行通信。 基站无线电站（21,22和23）通过光纤连接到中央基站（100）。 中央基站连接到移动交换中心（50）。 每个基站广播台设置有O / E转换器（201）和E / O转换器（207）。 O / E转换器将包含语音信号和呼叫连接控制信号的光信号转换成RF信号。 E / O转换器（207）将从移动终端（11）经由天线（204）接收的RF信号转换为光信号，并将光信号发送到中央基站。 中央基站包括用于将来自每个基站的光信号转换为RF信号的O / E转换器（301-303） 接收器（401-403），用于解调这些RF信号; 发射机（406-408），用于将来自移动交换中心的语音信号和呼叫连接控制信号转换成RF信号; 和用于将这些RF信号转换为光信号并将光信号发送到基站的E / O转换器（304-306）。

    Optical transmission system and optical network terminals used therein
    2.
    发明授权
    Optical transmission system and optical network terminals used therein 失效
    其中使用的光传输系统和光网络终端

    公开(公告)号：US5751455A

    公开(公告)日：1998-05-12

    申请号：US742685

    申请日：1996-10-31

    申请人： Makoto Shibutani ,  Katsumi Emura

    发明人： Makoto Shibutani ,  Katsumi Emura

    IPC分类号： H04B10/50 ,  H04B10/54 ,  H04B10/572 ,  H04B10/58 ,  H04J14/02

    CPC分类号： H04J14/0298 ,  H04B10/5051 ,  H04B10/54 ,  H04B10/572 ,  H04B10/58

    摘要： An optical transmission system of an N : 1 or an N:N type is provided, in which there is no deterioration caused by beat noise between signals. A plurality of optical modulators are cascaded in an optical fiber transmission path having a light source and a plurality of light receivers connected to two respective ends of the optical fiber transmission path, and carrier waves having frequencies respectively different are applied to the optical modulators. This enables the light receivers to receive a radio frequency signal in which the carrier waves are frequency-multiplexed. The light receivers receive only the signal beam so that there is no occurrence of beat noise. In another arrangement, at the optical network terminal, a part of a signal beam is split and the split beam is intensity-modulated responsively to carrier waves by an optical modulator and, thereafter, is combined again to a passing beam. It is possible to obtain at the signal beam receiver a received signal in which carrier waves from respective optical network terminals are frequency-multiplexed. This prevents occurrence of inter-modulation distortion in the cascaded optical modulators.

    摘要翻译： 提供了N：1或N：N型的光传输系统，其中不会由于信号之间的差拍引起的劣化。 多个光调制器在具有光源和连接到光纤传输路径的两个相应端的多个光接收器的光纤传输路径中级联，并且将具有不同频率的载波应用于光调制器。 这使得光接收器能够接收其中载波被频率复用的射频信号。 光接收器仅接收信号光束，从而不发生拍频噪声。 在另一种布置中，在光网络终端，信号光束的一部分被分离，并且分离光束通过光学调制器响应于载波进行强度调制，然后再次被合并到通过光束。 可以在信号波束接收机处获得来自各个光网络终端的载波被频率复用的接收信号。 这防止级联光调制器中的互调失真的发生。

    Optical network
    4.
    发明授权
    Optical network 失效
    光网络

    公开(公告)号：US5771111A

    公开(公告)日：1998-06-23

    申请号：US573321

    申请日：1995-12-15

    申请人： Wataru Domon ,  Makoto Shibutani

    发明人： Wataru Domon ,  Makoto Shibutani

    IPC分类号： H04J14/00 ,  H04B10/27 ,  H04B10/272 ,  H04B10/275 ,  H04B10/29 ,  H04B10/297 ,  H04J14/02

    CPC分类号： H04J14/0298

    摘要： Disclosed is an optical network which has a plurality of subordinate optical networks, each of which being connected with a plurality of optical terminals which function as a transmitter and a receiver of a signal light, wherein multiplexing of transmission signals and demultiplexing of reception signals at the optical terminals are carried out in the subcarrier multiplexing manner; and a main optical network which is connected with the subordinate optical networks, wherein multiplexing of signal lights transmitted from the subordinate optical networks is carried out in the wavelength division multiplexing manner.

    摘要翻译： 公开了一种光网络，其具有多个从属光网络，每个光网络与用作信号光的发射机和接收机的多个光学终端连接，其中传输信号的复用和接收信号的解复用 以子载波复用方式执行光终端; 以及与下级光网络连接的主光网络，其中从下级光网络发送的信号光的复用以波分复用方式进行。

    Frequency stabilization of a laser beam by using a birefrigent body
    5.
    发明授权
    Frequency stabilization of a laser beam by using a birefrigent body 失效
    激光束的频率稳定性使用双极体

    公开(公告)号：US5107512A

    公开(公告)日：1992-04-21

    申请号：US575719

    申请日：1990-08-31

    申请人： Makoto Shibutani

    发明人： Makoto Shibutani

    IPC分类号： H04B10/572 ,  H01S5/068 ,  H01S5/0687 ,  H04B10/07 ,  H04B10/25 ,  H04B10/293 ,  H04B10/564

    CPC分类号： H01S5/0687

    摘要： To supply a frequency control signal to a laser diode module for generating a laser beam susceptible to a variation in frequency or wavelength, a frequency stabilizing device comprises a birefringent body (21) for converting the variation to a variation in a polarization state of the laser beam to produce a polarization varied beam, which a polarization separating element (22) separates into first and second beam components having orthogonally polarized directions and first and second beam intensities. Optical detectors (26,27) detect the beam intensities to produce first and second detection signals. A subtracter (28) calculates a difference between the beam intensities. A control signal producing arangement (29) produces the frequency control signal in compliance with the difference. Preferably, the difference is normalized by a sum of the beam intensities. The birefringent body may be a uniaxial or a biaxial body. The uniaxial body should have an optic axis which forms an angle of 45.degree. with a predetermined plane of polarization of the laser beam. In this event, the orthogonally polarized directions should be parallel and perpendicular to predetermined direction of polarization. It is possible to use the sum in stabilizing an output power of the laser diode module.

    Polarization diversity receiver having little deteriorated sensitivity despite use of a square-law demodulator having a restricted dynamic range
    9.
    发明授权
    Polarization diversity receiver having little deteriorated sensitivity despite use of a square-law demodulator having a restricted dynamic range 失效
    极化分集接收机尽管使用具有受限动态范围的平方律解调器，但灵敏度几乎不降低

    公开(公告)号：US4972515A

    公开(公告)日：1990-11-20

    申请号：US354558

    申请日：1989-05-22

    申请人： Makoto Shibutani

    发明人： Makoto Shibutani

    IPC分类号： G02F2/00 ,  H04B10/07 ,  H04B10/516 ,  H04B10/532 ,  H04B10/548 ,  H04B10/564 ,  H04B10/61 ,  H04B10/64

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

    摘要： In a polarization diversity receiver comprising demodulator circuits (31, 32) which may have a restricted dynamic range, input intermediate frequency signals are supplied from optical detectors (16, 17) to automatic gain controllers (21, 22) for producing output intermediate frequency signals with their intensities adjusted optimal to the respective demodulator circuits irrespective of a fluctuation which may appear in a polarization state of a signal beam supplied to the receiver. Supplied with the output intermediate frequency signals, the demodulator circuits deliver baseband signals to a signal combiner (43) with their intensities adjusted so as to have a ratio which is equal to a square of a ration between intensities of the input intermediate frequency signals. This makes the receiver have a reception sensitivity which is least deteriorated by polarization diversity. Each automatic gain controller comprises a variable gain adjuster (26, 28) which may be either feed forward or feedback controlled by a control signal produced by an intensity detector (25, 27). Each demodulator circuit comprises another variable gain adjuster (41, 42) controlled by the control signal.