公开(公告)号：EP0838913A2

公开(公告)日：1998-04-29

申请号：EP97307814.0

申请日：1997-10-03

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron

IPC分类号： H04B10/155

CPC分类号： H04B10/505 ,  H04B10/503 ,  H04B10/506 ,  H04B10/564 ,  H04J14/0221

摘要： In an optical transmission system, an optical signal is transmitted to an optical element which is sensitive to changes in the optical power of the signal. Changes in optical power are anticipated and damped by controlling the transmitter output power, or an external damping element. For WDM systems, wavelengths can be added or removed without causing rapid changes in total power which would otherwise disturb the output of downstream optical amplifiers, and cause bit errors.

摘要翻译： 在光传输系统中，光信号被发送到对信号的光功率变化敏感的光学元件。 通过控制发射机输出功率或外部阻尼元件可以预期和减弱光功率的变化。 对于WDM系统，可以添加或去除波长，而不会导致总功率的快速变化，否则会干扰下游光放大器的输出，并导致位错误。

公开(公告)号：EP0820161A2

公开(公告)日：1998-01-21

申请号：EP97304488.6

申请日：1997-06-25

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron

IPC分类号： H04B10/08

CPC分类号： H04B10/0795 ,  H04B10/07951

摘要： In an optical transmission system, multi-path interference is distinguished from the desired signal and other interferences, by measuring light transmitted from a source, using an element of the transmission system. Frequency modulation products are used, and the signature of the interference in the frequency spectrum is derived.

摘要翻译： 在光传输系统中，通过使用传输系统的元件测量从源发射的光，将多路径干扰与期望的信号和其他干扰区分开。 使用频率调制产物，导出频谱干扰的签名。

公开(公告)号：EP0863626A3

公开(公告)日：1999-12-08

申请号：EP98300773.3

申请日：1998-02-03

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron ,  Robinson, Alan ,  Epworth, Richard Edward ,  Harvey, Henry John

IPC分类号： H04B10/08

CPC分类号： H04B10/2572 ,  H04B10/07951 ,  H04B10/2569

摘要： An Optical Transmission System (1) includes a monitor (8) for outputting monitored data (a) representative of the extent to which an optical signal is degraded by polarization mode dispersion. The monitor measures the degree of depolarization (U) present in a sample of the optical signal derived from an optical tap (10), the depolarization being associated with polarization variation at the bit rate frequency of a signal data stream carried by the optical signal. The monitored data is used to control operation of the system to reroute the optical path taken by the optical signal in the event of a threshold level of polarization mode dispersion being exceeded. A transmitter (2) of the optical signal may also be controlled to minimize polarization mode dispersion by varying the polarization state of the optical signal at launch so as to reduce the measured monitored data. The monitor functions during normal transmission of optical signals without the need for shutting down links of the system for measurement purposes. The invention has particular application to long haul optical transmissions of data streams at 10 Gb/sec or more.

公开(公告)号：EP0849893A2

公开(公告)日：1998-06-24

申请号：EP97309355.2

申请日：1997-11-20

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron

IPC分类号： H04B10/08

CPC分类号： H04B10/2563 ,  H04B10/077 ,  H04B10/07955

摘要： An optical transmission system comprises a number of optical terminals connected by optical waveguides such as optical fibres. Nonlinear processes occurring within an optical transmission medium of the waveguide or within the optical terminals is detected by a monitor which outputs monitored data representative of the products of nonlinearity. The data is used to control the power of the optical signal such that power is regulated to avoid the onset of the nonlinear process. The data may also be used to indicate an alarm condition to an operator. A monitor for four wave mixing detection utilises dither signals applied to respective frequency components of a wavelength division multiplexed signal, products of the four wave mixing process being detected in the monitor by correlation between a sample of a received optical signal and reference data representative of dither induced modulation in the four wave mixing product. Mutually orthogonal dither wave forms are derived from pseudo-random sequences and applied as low frequency modulations to transmitted optical signals. Such monitors allow optical power to be controlled and assist in locating defective equipment requiring remedial action. The invention has application to long haul optical transmission systems.

摘要翻译： 光传输系统包括通过诸如光纤之类的光波导连接的多个光学终端。 在波导的光传输介质或光端点内发生的非线性处理由监视器检测，监视器输出代表非线性的乘积的监视数据。 该数据用于控制光信号的功率，使得调节功率以避免非线性处理的开始。 数据也可以用于向操作者指示警报状况。 用于四波混频检测的监视器利用施加到波分多路复用信号的相应频率分量的抖动信号，通过接收的光信号的采样和表示抖动的参考数据之间的相关性，在监视器中检测四波混频处理的乘积 在四波混合产物中诱导调制。 相互垂直的抖动波形从伪随机序列导出，并作为低频调制应用于传输的光信号。 这种监视器允许控制光功率，并有助于定位需要补救动作的有缺陷的设备。 本发明适用于长距离光传输系统。

公开(公告)号：EP0813349A2

公开(公告)日：1997-12-17

申请号：EP97304025.6

申请日：1997-06-10

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron

IPC分类号： H04Q11/00 ,  H04B10/08

CPC分类号： H04Q11/0005 ,  H04Q2011/0011 ,  H04Q2011/0015 ,  H04Q2011/0043 ,  H04Q2011/0049 ,  H04Q2011/0081 ,  H04Q2011/0083

摘要： A verification system for a switch or other element in a digital transmission system includes a sample extraction means for tapping a input to the switch, and a similar means for tapping an output of the switch. Analogue features of the signal passing through the switch are tapped off and compared by pattern matching without demultiplexing digital data from the signal passing through the switch. The result of the match can be used to verify the switch has switched correctly, or to monitor other parameters such as cross-talk.

摘要翻译： 用于数字传输系统中的开关或其他元件的验证系统包括用于轻敲开关的输入的采样提取装置以及用于轻敲开关的输出的类似装置。 通过开关的信号的模拟特征被分出，并通过模式匹配进行比较，而不通过开关信号解复用数字数据。 匹配结果可用于验证交换机是否正确切换，或用于监控其他参数，如串扰。

公开(公告)号：EP0884868A2

公开(公告)日：1998-12-16

申请号：EP98303661.7

申请日：1998-05-11

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron

IPC分类号： H04L1/20 ,  H04B10/00

CPC分类号： H04L1/20

摘要： A pulsed optical signal (13) of a network (23) is monitored to obtain eye measurement data as a means of obtaining an indication of signal degradation. Optical sampling of the optical signal is effected by means of an interferometer (2) in which sampling optical pulses (8) are propagated equally through arms (3) and (4) of the interferometer which include semiconducter optical amplifiers (5,6). The optical signal to be monitored is counter propagated through one arm of the interferometer, thereby setting an interference condition of the interferometer by cross modulation in one of the semiconductor optical amplifiers. The output is detected and converted to electrical signals which are processed to obtain the eye measurement data. Parameters defining the quality of the eye are extracted and processed to locate defects occurring within a network by deploying eye monitors (20,21,22) at a number of locations (A,B,C). Elements (A,B,C) of the network may be controlled using the output parameters.

摘要翻译： 监测网络（23）的脉冲光信号（13）以获得眼睛测量数据作为获得信号劣化的指示的手段。 通过干涉仪（2）实现光学信号的光学采样，其中采样光脉冲（8）通过包括半导体光放大器（5,6）的干涉仪的臂（3）和（4）均匀地传播。 要监视的光信号通过干涉仪的一个臂进行反向传播，从而通过在其中一个半导体光放大器中的交叉调制来设置干涉仪的干涉条件。 输出被检测并转换成电信号，被处理以获得眼睛测量数据。 通过在多个位置（A，B，C）处部署眼睛监视器（20,21,22）来提取和处理定义眼睛质量的参数以定位在网络内发生的缺陷。 可以使用输出参数来控制网络的元素（A，B，C）。

公开(公告)号：EP0884867A2

公开(公告)日：1998-12-16

申请号：EP98303540.3

申请日：1998-05-06

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron

IPC分类号： H04B10/18

CPC分类号： H04B10/299 ,  H04B10/25133 ,  H04B10/2557 ,  H04B10/2569 ,  H04B10/2914

摘要： Data carrying optical signals (16) are subjected to equalisation or pulse shaping of the optical signal waveform. A plurality of optical tap signals (20,21) derived from the optical signal are used to control a modulator (5) operating on an input signal (50) to provide an output signal (22) having the desired waveform (D). A Mach-Zehnder interferometer (5) having semiconductor optical amplifiers (8,9) in each arm (6,7) provides modulation by the effect of cross modulation induced by propagating the respective tap signals through a selected one of the semiconductor optical amplifiers. Various forms of transversal filter are provided by selecting the number of optical taps, assigning positive or negative weights and appropriate delays. The effects of dispersion in optical signals can be mitigated by utilising optical taps with negative weights to subtract tail portions from the leading and trailing edges of a signal pulse. The invention has application to systems with high bit rates where equalisation or pulse shaping in the electrical domain is difficult to implement.

摘要翻译： 承载光信号（16）的数据经受光信号波形的均衡或脉冲整形。 使用从光信号导出的多个光抽头信号（20,21）来控制在输入信号（50）上工作的调制器（5），以提供具有期望波形（D）的输出信号（22）。 在每个臂（6,7）中具有半导体光放大器（8,9）的马赫 - 策德尔干涉仪（5）通过通过所选择的一个半导体光放大器传播各个抽头信号而引起的交叉调制的效果来提供调制。 通过选择光学抽头的数量，分配正负权重和适当的延迟来提供各种形式的横向滤波器。 通过使用具有负权重的光学抽头可以减少信号脉冲的前沿和后沿的尾部，可以减轻光信号中色散的影响。 本发明适用于具有高比特率的系统，其中电域中的均衡或脉冲整形难以实现。

公开(公告)号：EP0863626A2

公开(公告)日：1998-09-09

申请号：EP98300773.3

申请日：1998-02-03

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron ,  Robinson, Alan ,  Epworth, Richard Edward ,  Harvey, Henry John

IPC分类号： H04B10/08

CPC分类号： H04B10/2572 ,  H04B10/07951 ,  H04B10/2569

摘要： An Optical Transmission System (1) includes a monitor (8) for outputting monitored data (a) representative of the extent to which an optical signal is degraded by polarization mode dispersion. The monitor measures the degree of depolarization (U) present in a sample of the optical signal derived from an optical tap (10), the depolarization being associated with polarization variation at the bit rate frequency of a signal data stream carried by the optical signal. The monitored data is used to control operation of the system to reroute the optical path taken by the optical signal in the event of a threshold level of polarization mode dispersion being exceeded. A transmitter (2) of the optical signal may also be controlled to minimize polarization mode dispersion by varying the polarization state of the optical signal at launch so as to reduce the measured monitored data. The monitor functions during normal transmission of optical signals without the need for shutting down links of the system for measurement purposes. The invention has particular application to long haul optical transmissions of data streams at 10 Gb/sec or more.

摘要翻译： 光传输系统（1）包括用于输出监视数据（a）的监视器（a），（a）表示光信号被偏振模色散降低的程度。 监视器测量从光学抽头（10）导出的光学信号的采样中存在的去极化度（U），去偏振与由光信号承载的信号数据流的比特率频率处的偏振变化相关联。 所监视的数据用于控制在超过偏振模色散的阈值水平的情况下系统的操作以重新路由光信号所采取的光路。 也可以通过改变发射时的光信号的偏振状态来控制光信号的发射器（2），以使偏振模色散最小化，从而减少测量的监视数据。 监视器在光信号的正常传输期间起作用，而不需要关闭系统的链路用于测量目的。 本发明特别适用于10Gb /秒以上的数据流的长距离光传输。

公开(公告)号：EP0849622A3

公开(公告)日：1999-10-13

申请号：EP97309354.5

申请日：1997-11-20

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron ,  Hadjifotiou, Anagnostis

IPC分类号： G02F1/35 ,  H04B10/17 ,  H04L7/00

CPC分类号： H04B10/50 ,  G02F1/3517 ,  G02F2/004 ,  G02F2002/006 ,  H04B10/299 ,  H04J14/08 ,  H04L7/0075 ,  H04L7/027 ,  H04L7/033

摘要： An interferometer, such as a Mach-Zehnder type is fed with a pulse train. One arm is fed with a data stream, so as to modulate the pulse train according to the data stream. This enables the data stream to be regenerated, or sampled without converting from optical form into electrical form. Thus all optical regeneration, multiplexing, demultiplexing or retiming to remove jitter, can be achieved. An optical amplifier (20) in one arm of the interferometer enables the interference condition of the interferometer to be varied, to cause the pulse train to be modulated by the data.

公开(公告)号：EP0849622A2

公开(公告)日：1998-06-24

申请号：EP97309354.5

申请日：1997-11-20

申请人： NORTHERN TELECOM LIMITED

发明人： Roberts, Kim Byron ,  Hadjifotiou, Anagnostis

IPC分类号： G02F1/35 ,  H04B10/17 ,  H04L7/00

CPC分类号： H04B10/50 ,  G02F1/3517 ,  G02F2/004 ,  G02F2002/006 ,  H04B10/299 ,  H04J14/08 ,  H04L7/0075 ,  H04L7/027 ,  H04L7/033

摘要： An interferometer, such as a Mach-Zehnder type is fed with a pulse train. One arm is fed with a data stream, so as to modulate the pulse train according to the data stream. This enables the data stream to be regenerated, or sampled without converting from optical form into electrical form. Thus all optical regeneration, multiplexing, demultiplexing or retiming to remove jitter, can be achieved. An optical amplifier (20) in one arm of the interferometer enables the interference condition of the interferometer to be varied, to cause the pulse train to be modulated by the data.

摘要翻译： 诸如Mach-Zehnder型干涉仪馈送脉冲串。 一臂供给数据流，以便根据数据流调制脉冲序列。 这使得数据流能够被再生或采样，而不会将光学形式转换成电形式。 因此，可以实现所有的光学再生，多路复用，解复用或重定时以消除抖动。 干涉仪的一个臂中的光放大器（20）能够使干涉仪的干涉条件变化，从而使脉冲序列被数据调制。