-
公开(公告)号：US06271942B1
公开(公告)日：2001-08-07
申请号：US08978820
申请日：1997-11-26
IPC分类号： H04J1402
CPC分类号： H04B10/564 , H04B10/504 , H04B10/572 , H04B10/58
摘要： An oscillator outputs an additional signal with a frequency which is higher than a frequency corresponding to a bandwidth of a frequency band allotted to an electrical signal to be transmitted and lower than a half of a lowest frequency of a frequency band allotted to the electrical signal to be transmitted. Thereby, if a second order intermodulation distortion between the additional signal and the electrical signal to be transmitted occurs, a frequency where distortion occurs is outside all of the frequency bands allotted to the electrical signal to be transmitted, and the occurring second order intermodulation distortion does not affect the electrical signal to be transmitted. Further, if the second order intermodulation distortion of the additional signal occurs, the frequency where distortion occurs is outside all of the frequency bands allotted to the electrical signal to be transmitted, and the occurring second order intermodulation distortion does not affect the electrical signal to be transmitted. Not only noise and distortions caused by reflected optical signal but also OBI noise can be reduced by using the additional signal.
摘要翻译： 振荡器输出一个附加信号，该信号的频率高于分配给要发送的电信号的频带的带宽的频率，并且低于分配给电信号的频带的最低频率的一半， 被传送。 因此，如果发生附加信号和要发送的电信号之间的二阶互调失真，则发生失真的频率在分配给要发送的电信号的所有频带之外，并且发生的二阶互调失真 不影响要传输的电信号。 此外，如果发生附加信号的二阶互调失真，则发生失真的频率在分配给要发送的电信号的所有频带之外，并且发生的二阶互调失真不影响电信号 传输。 不仅可以通过使用附加信号来减少由反射光信号引起的噪声和失真，而且可以减少OBI噪声。
-
2.发明授权Catv system in which chanel selection signal is transmitted from the subscriber location 失效从用户位置发送通道选择信号的Catv系统
公开(公告)号：US5729281A
公开(公告)日：1998-03-17
申请号：US443699
申请日：1995-05-18
IPC分类号： H04H20/38 , H04H20/76 , H04H20/77 , H04H20/78 , H04H60/90 , H04N7/173 , H04N21/222 , H04N21/437 , H04N21/61 , H04N21/647 , H04N21/6587 , H04N7/14
摘要： A center station 1 generates an all-channel signal 2 obtained by multiplexing signals on all channels, and transmits the signals to a selective distribution station 10 through 1 wire transmission line such as an optical fiber. Subscribers' transmitting devices 40.sub.1 to 40.sub.N transmit requests for channels to be received by corresponding subscribers' receiving devices 30.sub.1 to 30.sub.N to the selective distribution station 10 in a radio transmission system. The selective distribution station 10 selects the signals on the channels requested from the all-channel signal 2 in response to requests to receive channels serving as up-signals transmitted in a radio transmission system from the subscribers' transmitting devices 40.sub.1 to 40.sub.N, and distributes and transmits the selected signals to the subscribers' receiving devices 30.sub.1 to 30.sub.N as down-signals.
摘要翻译： 中心站1产生通过在所有信道上复用信号而获得的全信道信号2，并且通过诸如光纤的1线传输线将信号发送到选择分配站10。 订户发送装置401〜40N向无线传送系统中的选择性分发站10发送要由相应的用户接收装置301〜30N接收的信道的请求。 选择分配站10响应于从用户的发送设备401到40N在无线电传输系统中发送的用作接收信道的信道的请求，选择从全信道信号2请求的信道上的信号，并且 将所选择的信号作为下行信号发送到用户接收装置301〜30N。
-
3.发明授权
公开(公告)号：US5532865A
公开(公告)日：1996-07-02
申请号：US526578
申请日：1995-09-11
IPC分类号： H04B10/155 , H04J14/02 , H04B10/06 , H04B10/04
CPC分类号： H04J14/02 , H04B10/506 , H04B10/564 , H04B10/572
摘要： In a fiber optic communication terminal composed of a light mixing part for mixing an input light signal and a light signal from own station, a detecting part for picking up a part of the output of the light mixing part to detect its quality deterioration, and a light source part in which the wavelength of output light is variable, increase of noise level or occurrence of bit error due to beat interference caused by mixing of input light signal and light signal from the own station is detected as quality deterioration in the detecting part, and by controlling the wavelength of the light source part accordingly, generation of beat interference can be prevented, and moreover by using a fiber optic communication terminal capable of maintaining the wavelength so that the signal quality may be the set value, the output light wavelength can be arranged at high density on the whole as a fiber optic communication system.
摘要翻译： 在由用于混合输入光信号的光混合部分和来自本站的光信号组成的光纤通信终端中，检测部分用于拾取光混合部分的输出的一部分以检测其质量劣化，以及 作为检测部的质量恶化，检测输出光的波长可变的光源部分，噪声电平的增加或由于输入光信号的混合引起的拍频干扰和来自本台的光信号的位误差的发生， 并且通过相应地控制光源部分的波长，可以防止产生拍频干扰，此外，通过使用能够保持波长的光纤通信终端，使得信号质量可以是设定值，输出光波长可以 作为光纤通信系统，整体上以高密度排列。
-
4.发明授权Method for measuring distance between reflection points along light transmission line and reflectance thereof 失效测量沿光传输线的反射点之间的距离及其反射率的方法
公开(公告)号：US5644389A
公开(公告)日：1997-07-01
申请号：US557478
申请日：1995-11-14
IPC分类号： G01M11/02 , G01M11/00 , H04B10/07 , H04B10/077 , H04B10/079 , H04B10/54 , G01N21/88
CPC分类号： G01M11/333 , G01M11/335
摘要： A signal for which the amplitude of envelope becomes substantially 0 only for a certain period of time within the time of a period T, and a measured signal having a certain amplitude are synthesized, and the synthesized signal is optically transmitted. When a plurality of reflection points are present on a light transmission line, there is an increase in harmonic distortion or intermodulation distortion as well as in cross modulation distortion after receiving. This increase in cross modulation distortion causes an increase in variation of amplitude of the measured signal. In such a case, it is possible to calculate the distance between, and/or reflectance of, reflection points present on end faces of optical elements and/or connecting points of optical fibers on the light transmission line by investigating first periodical characteristics of variation of the transmitted measured signal during transmission relative to the change in central light frequency of the signal light, or investigating second periodical characteristics of variation of the transmitted measured signal during transmission corresponding to the change in the frequency of the measured signal.
摘要翻译： 在周期T的时间内，信号的幅度变为基本为0的信号在一段时间内被合成，并且合成具有一定幅度的测量信号，并且合成信号被光学传输。 当在光传输线上存在多个反射点时，谐波失真或互调失真以及接收后的交叉调制失真增加。 交叉调制失真的这种增加导致测量信号的幅度变化的增加。 在这种情况下，可以通过调查光传输线上的光学元件的端面和/或光纤的连接点上的反射点之间的距离和/或反射率来计算第一周期特性 在传输期间发射的测量信号相对于信号光的中心光频率的变化，或者调查在传输期间发射的测量信号的变化的第二周期特性，对应于测量信号的频率的变化。
-
5.发明授权
公开(公告)号：US5850303A
公开(公告)日：1998-12-15
申请号：US775247
申请日：1996-12-30
IPC分类号： H04B10/155 , H04J14/02 , H04B10/04
CPC分类号： H04J14/02 , H04B10/504 , H04B10/506 , H04J14/0224
摘要： A signal processing circuit 113 subjects a transmission signal outputted from a signal source 111 and a carrier outputted from a carrier generation circuit 112 to predetermined signal processing, to generate a modulation signal amplitude-modulated by the transmission signal and so adapted that its envelop on the high level side (or on the low level side) has a shape analogous to the waveform of the transmission signal and its envelope on the low level side (or on the high level side) is at an approximately constant level. A light source 114 converts the modulation signal into a light intensity modulation signal, and outputs the light intensity modulation signal to an optical coupler 120. The above-mentioned signal processing is performed by the signal processing circuit 113, whereby the spectrum distribution of the light signal outputted from the light source 114 is dispersed, and the peak value of light spectra is decreased. The peak value of beat noise produced after receiving is proportional to the peak value of the light spectra, whereby the peak value of the beat noise is also decreased.
摘要翻译： 信号处理电路113对从信号源111输出的发送信号和从载波生成电路112输出的载波进行规定的信号处理，生成由发送信号进行了幅度调制的调制信号， 高电平侧（或低电平侧）具有与发送信号的波形类似的形状，并且其低电平侧（或高电平侧）的包络处于大致恒定的水平。 光源114将调制信号转换为光强度调制信号，并将光强度调制信号输出到光耦合器120.由信号处理电路113进行上述信号处理，由此光的频谱分布 从光源114输出的信号被分散，光谱的峰值减小。 接收后产生的拍噪噪声的峰值与光谱的峰值成比例，从而峰值噪声也降低。
-
6.发明授权Cable broadcasting system and the transmission center for on demand program services 失效有线广播系统和按需节目服务的传输中心
公开(公告)号：US5339315A
公开(公告)日：1994-08-16
申请号：US887475
申请日：1992-05-22
申请人： Kazuki Maeda , Kuniaki Utsumi , Katsuyuki Fujito
发明人： Kazuki Maeda , Kuniaki Utsumi , Katsuyuki Fujito
IPC分类号： H04H20/16 , H04H20/33 , H04H20/69 , H04H20/76 , H04H60/15 , H04H60/23 , H04N7/16 , H04N7/173 , H04N7/22 , H04N21/2365 , H04N21/238
CPC分类号： H04H60/15 , H04H20/16 , H04H20/33 , H04H20/69 , H04H20/76 , H04H60/16 , H04H60/23 , H04N21/2383 , H04N21/4382 , H04N7/163 , H04N7/17336 , H04N7/22
摘要： The present invention provides a cable broadcasting system and the transmission center employed therein. In the transmission center, plural images are divided into several groups in the same kinds and each image in one kind is repeated not simultaneously so that they are outputted as independent plural image signals, and the image that the subscribers have requested is selected from those plural image signals which is enciphered, modulated, and multiplexed to be transmitted in optical transmission lines through an available channel to the subscribers, while the transmission channel is validated as well as the enciphered image signal is deciphered at the subscribers' end in order to enable the subscribers to watch the image they have requested.
摘要翻译： 本发明提供一种有线广播系统及其中采用的传输中心。 在传输中心，将多个图像分成相同种类的几个组，并且一个类型的每个图像不被同时重复，使得它们作为独立的多个图像信号输出，并且从多个图像中选择用户已经请求的图像 图像信号被加密，调制和多路复用以在光传输线路中通过可用信道发送给用户，而传输信道被验证，并且加密的图像信号在用户端被解密，以使得能够 订阅者观看他们要求的图像。
-
公开(公告)号：US5875049A
公开(公告)日：1999-02-23
申请号：US803927
申请日：1997-02-24
CPC分类号： H03F3/08 , H03F3/45475 , H03F3/45982 , H04B10/6933
摘要： The present invention provides an amplifier capable of accurately reproducing a signal under various operating environments and an optical receiving circuit using the amplifier. The differential amplifier is constructed such that the amplification factor thereof is set to 0.5, and a variation occurring inside thereof is the same as a variation occurring inside of the differential amplifier. Respective output variations occurring in maximum value holding circuits due to a temperature variation and a power supply voltage variation are canceled by providing differential amplification in the differential amplifier. At this time, an output variation occurring in the differential amplifier is also canceled. Therefore, an output variation occurring in the differential amplifier is made equal in value to the output variation occurring in the differential amplifier, such that the same variation as a signal input is superimposed on the reference input fed to the differential amplifier. consequently, a reference input accurately following the DC level of the signal input can be fed to the differential amplifier, whereby stable amplification can always be provided.
摘要翻译： 本发明提供一种能够在各种操作环境下准确再现信号的放大器和使用放大器的光接收电路。 差分放大器被构造为使其放大系数设定为0.5，并且其内部的变化与差分放大器内部发生的变化相同。 通过在差分放大器中提供差分放大来消除由于温度变化和电源电压变化而在最大值保持电路中发生的各自的输出变化。 此时，差分放大器中出现的输出变化也被取消。 因此，使差分放大器中发生的输出变化值与差分放大器中出现的输出变化值相等，使得与馈送到差分放大器的参考输入相同的信号输入变化相加。 因此，准确跟随信号输入的DC电平的参考输入可以被馈送到差分放大器，由此可以总是提供稳定的放大。
-
8.发明授权
公开(公告)号：US5530583A
公开(公告)日：1996-06-25
申请号：US342437
申请日：1994-11-18
申请人： Tomoaki Uno , Jun Ohya , Katsuyuki Fujito
发明人： Tomoaki Uno , Jun Ohya , Katsuyuki Fujito
CPC分类号： H01S3/06754 , H01S3/094011
摘要： The optical signal amplification apparatus of this invention includes a plurality of optical fiber amplifiers connected in series, each optical fiber amplifier including: an optical fiber doped with rare earth ions; and a pumping light source for emitting pumping light for exciting the optical fiber, wherein the power of signal light input into each optical fiber amplifier is set so that the value of a distortion component of the signal light output from the optical fiber amplifier is equal to the value of a distortion component of the signal light input into the optical fiber amplifier and that the distortion component of the signal light output from the optical fiber amplifier increases when the power of the signal light input into the optical fiber amplifier increases. An optical fiber transmission system including the optical signal amplification device is also provided.
摘要翻译： 本发明的光信号放大装置包括串联连接的多个光纤放大器，每个光纤放大器包括：掺杂有稀土离子的光纤; 以及用于发射用于激励光纤的泵浦光的泵浦光源，其中输入到每个光纤放大器的信号光的功率被设置为使得从光纤放大器输出的信号光的失真分量的值等于 当输入到光纤放大器的信号光的功率增加时，输入到光纤放大器的信号光的失真分量的值和从光纤放大器输出的信号光的失真分量增加。 还提供了包括光信号放大装置的光纤传输系统。
-
公开(公告)号：US4722081A
公开(公告)日：1988-01-26
申请号：US753620
申请日：1985-07-10
CPC分类号： G02B6/3822 , G02B6/3825 , G02B6/4207
摘要： An optical transmission system is disclosed wherein a multiplexed analog signal is supplied to a laser diode to modulate the intensity of a long-wavelength laser beam. A single mode optical fiber transmission medium has a first inclined end face at a proximal end and a second inclined end face at a distal end. The laser beam is coupled to the proximal end of the transmission medium by a coupling means including a single mode optical fiber connecting medium having one end connected to the laser diode and an opposite end having a third inclined end face complementary to the first inclined end face and a coupler for coupling the first and third inclined end faces in abutment relation. An optoelectrical transducer having a light receiving face is located adjacent the distal end of the transmission medium, the light receiving face being parallel to the second inclined end face of the transmission medium to divert rays of light reflecting from the transducer away from the angle of reentry to the transmission medium.
摘要翻译： 公开了一种光传输系统，其中将复用的模拟信号提供给激光二极管以调制长波长激光束的强度。 单模光纤传输介质在近端具有第一倾斜端面和在远端具有第二倾斜端面。 激光束通过耦合装置耦合到传输介质的近端，该耦合装置包括单模光纤连接介质，其一端连接到激光二极管，另一端具有与第一倾斜端面互补的第三倾斜端面 以及用于将所述第一和第三倾斜端面以邻接关系联接的联接器。 具有光接收面的光电传感器位于传输介质的远端附近，光接收面平行于传输介质的第二倾斜端面，以将从换能器反射的光线转向远离折返角 传输介质。
-
公开(公告)号：US4449188A
公开(公告)日：1984-05-15
申请号：US318552
申请日：1981-11-05
CPC分类号： G01R27/2605 , G01N27/223 , Y10T307/779
摘要： Apparatus for controlling humidity comprises a humidity sensing circuit including a humidity sensing element the electrostatic capacitance of which varies in accordance with the ambient relative humidity, and an air-conditioning system responsive to the sensed humidity. The humidity sensing element is charged and discharged repeatedly in accordance with a pulse train signal, and a period required for the voltage across the sensing element is measured during charging by a comparison between the voltage and a reference voltage. The pulse width or the reference voltage may be changed to select a desired reference humidity. A hysteresis characteristic may be given to render the operation of the circuit stable. When an SCR is controlled by the output signal of the humidity sensing circuit, the frequency of the pulse train signal is selected to be greater than four times the frequency of the voltage applied to the SCR.
摘要翻译： 用于控制湿度的装置包括湿度感测电路，其包括其静电电容根据环境相对湿度而变化的湿度感测元件，以及响应于感测到的湿度的空调系统。 湿度感测元件根据脉冲串信号重复充电和放电，并且通过电压和参考电压之间的比较在充电期间测量感测元件两端的电压所需的周期。 可以改变脉冲宽度或参考电压以选择所需的参考湿度。 可以给出滞后特性以使电路的操作稳定。 当SCR由湿度检测电路的输出信号控制时，脉冲序列信号的频率被选择为大于施加到SCR的电压频率的四倍。
-
-
-
-
-
-
-
-
-
搜索结果
17 条记录 (耗时 0.023 秒)
