Method for secure signal transmission in a telecommunication network, in particular in a local area network
    2.
    发明申请
    Method for secure signal transmission in a telecommunication network, in particular in a local area network 有权
    在电信网络中,特别是在局域网中用于安全信号传输的方法

    公开(公告)号:US20090204805A1

    公开(公告)日:2009-08-13

    申请号:US11664967

    申请日:2004-10-15

    IPC分类号: H04L9/00

    CPC分类号: H04L63/0485 H04W12/02

    摘要: In a telecommunication network, a modular expandable gateway connects a local area network to a wide area network and includes a base module and a plurality of add-on modules arranged in one or more stacks, the base module and the add-modules including respective encryption/decryption engines to exchange secure information with each other, thus frustrating any possible fraudulent interception of the information at the module interconnections.

    摘要翻译: 在电信网络中,模块化可扩展网关将局域网连接到广域网,并且包括基本模块和布置在一个或多个堆叠中的多个附加模块,基本模块和附加模块包括相应的加密 /解密引擎以彼此交换安全信息,从而使得在模块互连处的任何可能的欺诈性拦截信息受到挫败。

    Modulated and depolarized optical signal transmission system
    3.
    发明授权
    Modulated and depolarized optical signal transmission system 失效
    调制和去极化光信号传输系统

    公开(公告)号:US5910852A

    公开(公告)日:1999-06-08

    申请号:US759792

    申请日:1996-12-03

    CPC分类号: H04B10/2537 H04B10/532

    摘要: An optical communication system is described which includes an optical source; an optical modulator, receiving a transmission signal having frequencies included within a signal band and adapted to emit a modulated optical signal of a predetermined optical bandwidth; an optical transmission line comprising an optical fiber portion; and an optical receiver adapted to receive the optical signal in the presence of a predetermined SNR in the signal band, measured in a 5 MHz band. The telecommunication system further comprises, optically connected between the optical modulator and the optical transmission line, a depolarizer comprising two polarization-maintaining optical fiber portions, optically connected with each other in such a manner that the respective polarization axes form an angle of 45.degree., in which the optical bandwidth, lengths and birefringence of the polarization-maintaining optical fibers are operatively selected so that the SNR at the receiver in the signal band does not differ more than 1 dB from the SNR at the receiver measured in a band of 5 MHz by substituting the optical fiber portion of the transmission line with a passive attenuator of same attenuation.

    摘要翻译: 描述了包括光源的光通信系统; 光调制器,接收具有包括在信号频带内并且适于发射预定光带宽的调制光信号的频率的发射信号; 光传输线,包括光纤部分; 以及光接收机,其适于在存在以5MHz频带测量的信号频带中的预定SNR的情况下接收光信号。 电信系统还包括光连接在光调制器和光传输线之间的消偏振器,包括两个偏振保持光纤部分,它们以相应的偏振轴形成45°的角度彼此光学连接, 其中可操作地选择保偏光纤的光学带宽,长度和双折射,使得信号频带中的接收机处的SNR与在5MHz的频带中测量的接收机处的SNR相比不超过1dB 通过用相同衰减的无源衰减器代替传输线的光纤部分。

    Network for distributing signals to a plurality of users
    4.
    发明授权
    Network for distributing signals to a plurality of users 失效
    用于向多个用户发送信号的网络

    公开(公告)号:US06909821B2

    公开(公告)日:2005-06-21

    申请号:US10169167

    申请日:2000-12-27

    摘要: A network for distributing signals to a plurality of user apparatuses having a distribution unit with a plurality of ports, and a plurality of optical-fiber cables connected to the ports and suitable to make the plurality of ports of the distribution unit communicate with the plurality of user apparatuses. At least one of the plurality of optical-fiber cables is an electrically terminated optical cable having an optical cable with a single-mode optical fiber and an opto-electronic end portion mechanically and permanently connected to an end of the optical cable, and the opto-electronic end portion has an opto-electronic conversion device having an optic port optically aligned with and mechanically connected to, an end of the single-mode optical fiber.

    摘要翻译: 一种用于向具有多个端口的分配单元的多个用户装置发送信号的网络,以及连接到所述端口并适于使所述分配单元的多个端口与所述多个端口通信的多个光纤电缆 用户装置。 多根光纤电缆中的至少一根是具有光缆的电端接的光缆,该光缆具有单模光纤,光电端部机械地且永久地连接到光缆的一端,光电 电子端部具有光电转换装置,其具有与单模光纤的端部光学对准并机械连接的光端口。

    External optical modulation system comprising a predistorter
    5.
    发明授权
    External optical modulation system comprising a predistorter 失效
    外部光调制系统包括一个预失真器

    公开(公告)号:US06313701B1

    公开(公告)日:2001-11-06

    申请号:US09440681

    申请日:1999-11-12

    IPC分类号: H03F126

    CPC分类号: H04B10/58 H04B1/62 H04B10/505

    摘要: The present invention relates to a method and to a signal predistorter circuit for eliminiating the nonlinearities in the input/output characteristics of nonlinear stages, in particular for eliminating the third-order nonlinearities. More particularly, it relates to a method and to a predistorter circuit for external optical modulators of television signals. The method for predistortion of a signal of variable amplitude comprises the phases of: delivering the said signal to at least one first distorter circuit; biasing the said at least one first distorter circuit; distorting the said signal in the said at least one first distorter circuit; characterized in that the said phase of biasing the said at least one first distorter circuit comprises the phase of maintaining a substantially constant preset voltage value on varying the amplitude of the said signal at the said at least one first distorter circuit.

    摘要翻译: 本发明涉及一种用于消除非线性阶段的输入/输出特性中的非线性的方法和信号预失真器电路,特别是用于消除三阶非线性。 更具体地说,它涉及一种用于电视信号的外部光调制器的方法和预失真器电路。 用于预失真的可变幅度信号的方法包括以下阶段:将所述信号传送到至少一个第一变压器电路; 偏压所述至少一个第一变压器电路; 在所述至少一个第一变压器电路中使所述信号失真; 其特征在于,偏置所述至少一个第一变压器电路的所述相位包括在所述至少一个第一变压器电路上改变所述信号的振幅时保持基本恒定的预设电压值的相位。

    Bias system in an optical CATV modulator
    6.
    发明授权
    Bias system in an optical CATV modulator 失效
    光学CATV调制器中的偏置系统

    公开(公告)号:US5812297A

    公开(公告)日:1998-09-22

    申请号:US720463

    申请日:1996-09-30

    摘要: An analog-external-modulation optical, emitter is described which comprises an electro-optical modulator and a piloting circuit. The piloting circuit comprises a pilot-tone-generating circuit; an electric control signal generated by the optical signal coming out of the modulator and a predetermined bias voltage are fed to the input of a differential amplifier the output of which is added to the pilot tone to feed an electric input of the electro-optical modulator. The RF input of the analog electric signal is connected to a linearizer circuit to which the pilot-tone-generating circuit is also connected. The output of the linearizer circuit is sent to an electric input of the electro-optical modulator through a band-stop filter adapted to eliminate the pilot tone downstream of the linearizer circuit.

    摘要翻译: 描述了一种模拟 - 外部调制光学发射器,其包括电光调制器和导频电路。 导频电路包括导频音产生电路; 由调制器出来的光信号产生的电控信号和预定的偏置电压被馈送到差分放大器的输入端,差分放大器的输出被加到导频音上,以馈送电光调制器的电输入端。 模拟电信号的RF输入连接到导频音产生电路也连接到的线性化电路。 线性化电路的输出通过适于消除线性化电路下游导频的带阻滤波器发送到电光调制器的电输入端。