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公开(公告)号：US5412415A
公开(公告)日：1995-05-02
申请号：US941066
申请日：1992-10-13
CPC分类号： H04N7/22
摘要： Signals, such as television signals, are distributed from a head-end station via a fibre network. The signals are amplitude modulated on carriers at different frequencies, and the different carriers combined to form a composite analogue signal. In the head-end station the composite analogue signal is clipped to reduce the peak-to-mean ratio and the clipped composite signal is digitized. The resulting digital data is transmitted onto the fibre network and is received at an optical receiver. The optical receiver reconstitutes the composite analogue signal for reception by a termination. In one example the composite analogue signal has a bandwidth of one octave or less, and is digitized by sampling at a sampling rate below the Nyquist rate.
摘要翻译： PCT No.PCT / GB91 / 00568 Sec。 371日期：1992年10月13日 102（e）日期1992年10月13日PCT 1991年4月10日PCT PCT。 公开号WO91 / 15927 日期：1991年10月17日。信号，如电视信号，通过光纤网络从头端站分发。 信号在不同频率的载波上进行幅度调制，并且不同载波组合形成复合模拟信号。 在前端站中，复合模拟信号被削波以减小峰值平均比，并且限幅复合信号被数字化。 所得到的数字数据被传送到光纤网络上，并在光接收器处被接收。 光接收机通过终端重构复合模拟信号以进行接收。 在一个示例中，复合模拟信号具有一个八度或更小的带宽，并且通过以低于奈奎斯特速率的采样速率采样进行数字化。
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2.发明授权
公开(公告)号：US5283831A
公开(公告)日：1994-02-01
申请号：US915860
申请日：1992-08-03
CPC分类号： H04L25/03866 , H04J3/0611
摘要： In a data communication system a signal is coded with n-bit codewords, wherein n is an integer. The codewords are converted to a serial bit-stream and scrambled using a PRBS (Pseudo-Random Binary Sequence) from a PRBS generator (4). The PRBS sequence has a length n x m where m is an integer. At a receiver the serial data is descrambled using a corresponding binary sequence from a PRBS generator (5) matched to that in the transmitter. The descrambling data is decoded in a decoder (6) in synchronism with the binary sequence in the generator (5), thereby maintaining word alignment between the transmitter and the receiver.
摘要翻译： PCT No.PCT / GB91 / 00570 Sec。 371日期：1992年8月3日 102（e）日期1992年8月3日PCT 1991年4月10日PCT PCT。 公开号WO91 / 15910PC 日期为1991年10月17日。在数据通信系统中，信号用n位码字编码，其中n是整数。 码字被转换成串行比特流并使用PRBS（伪随机二进制序列）从PRBS生成器（4）进行加扰。 PRBS序列具有长度n×m，其中m是整数。 在接收机处，使用与发射机中匹配的PRBS发生器（5）的相应二进制序列对串行数据进行解扰。 解码数据在解码器（6）中与生成器（5）中的二进制序列同步地解码，从而保持发送器和接收器之间的字对齐。
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公开(公告)号：US5272556A
公开(公告)日：1993-12-21
申请号：US778998
申请日：1991-11-14
CPC分类号： H04N7/22
摘要： A system for distributing HDTV signals from a head station to a number of customer stations includes a single head-end optical source having a frequency f.sub.0 and a modulator arranged to receive light from the single optical source. The modulator modulates the light with a sub-carrier multiplex of n channels, where n is an integer greater than 2, the n channels having frequencies f.sub.1, f.sub.2 . . . f.sub.n. The frequencies are separated in frequency-space from each other and from f.sub.0. A broadband passive branched optical network is connected to the output of the modulator and arranged to distribute the modulated signal from the head station to a plurality of customer stations each having a coherent heterodyne receiver.
摘要翻译： PCT No.PCT / GB90 / 00827 Sec。 371日期：1991年11月14日 102（e）1991年11月14日PCT PCT 1990年5月25日PCT公布。 第WO90 / 14734号公报 日本1990年11月29日。用于从头站向多个客户站分配HDTV信号的系统包括具有频率f0的单个头端光源和被布置成从单个光源接收光的调制器。 调制器用n个通道的副载波复用来调制光，其中n是大于2的整数，n个通道具有频率f1，f2。 。 。 fn。 频率在频率空间中彼此和从f0分离。 宽带无源分支光网络连接到调制器的输出端，并且被布置成将来自头站的调制信号分配给每个具有相干外差接收机的多个客户站。
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公开(公告)号：US5245459A
公开(公告)日：1993-09-14
申请号：US773639
申请日：1991-11-18
CPC分类号： H04N7/22
摘要： A system for distributing interactive HDTV signals includes a head-end station and a number of customer stations. The head-end station includes at least one optical source. A bidirectional transmissive broadband passive branched optical network distributes HDTV signals from the head-end station to the customer stations. Each customer station includes an optical coupler arranged to couple the subscriber station to a respective arm of the optical network a coherent receiver including a local oscillator laser and a transmitter arranged to modulate light from the local oscillator laser with return data for transmission via the coupler onto the network. The head-end station also includes a broadband optical receiver arranged to receive and demodulate the return data received via the optical network.
摘要翻译： PCT No.PCT / GB90 / 00826 Sec。 371日期1991年11月18日 102（e）1991年11月18日，PCT提交1990年5月25日PCT公布。 WO90 / 14733 PCT出版物 日期：1990年11月29日。用于分发交互式HDTV信号的系统包括头端站和多个客户站。 前端站包括至少一个光源。 双向传输宽带无源分支光网络将HDTV信号从头端站分配到客户站。 每个客户站包括光耦合器，其被布置为将用户站耦合到光网络的相应臂，包括本地振荡器激光器的相干接收器和布置成用来调制来自本地振荡器激光器的光的发射器，具有经由耦合器传输的返回数据到 网络。 前端站还包括布置成接收和解调通过光网络接收的返回数据的宽带光接收机。
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公开(公告)号：US4975899A
公开(公告)日：1990-12-04
申请号：US235873
申请日：1988-08-17
申请人： David W. Faulkner
发明人： David W. Faulkner
IPC分类号： H04B10/272 , H04B10/50 , H04J3/06 , H04J14/08
CPC分类号： H04J14/08 , H04B10/272 , H04B10/50 , H04J3/0682
摘要： An optical communications network comprises a number of remote stations connected to a node by optical fiber transmission paths interconnected by power dividers, each remote station including an optical transmitter operating at a peak power and a low duty cycle for a short period. Typically the optical transmitter is enabled to transmit information for only 10% or less of the total time and for a maximum of 500 ns.
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公开(公告)号：US4815803A
公开(公告)日：1989-03-28
申请号：US870765
申请日：1986-06-26
申请人： David W. Faulkner , Peter Healey
发明人： David W. Faulkner , Peter Healey
CPC分类号： G02B6/3562 , G02F1/313 , G02B6/3546
摘要： A node of an optical transmission network, for example a local area network, has a combined by-pass switch and optical modulator. The by-pass switch and modulator (45) comprises an optical switching matrix with two non-intersecting waveguides (W1, W2) connected by a further waveguide (W3). The junctions between the non-intersecting waveguides and the further waveguide perform both modulation of an optical carrier signal and re-routeing of the transmission path along the network.
摘要翻译： 光传输网络的节点，例如局域网，具有组合的旁路开关和光调制器。 旁路开关和调制器（45）包括具有通过另外的波导（W3）连接的两个不相交的波导（W1，W2）的光学开关矩阵。 不相交的波导与另外的波导之间的接点执行光载波信号的调制和沿着网络的传输路径的重新路由。
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公开(公告)号：US5453865A
公开(公告)日：1995-09-26
申请号：US211411
申请日：1994-05-24
CPC分类号： H04B10/071 , H04B10/07
摘要： A system for monitoring a network in which a station is connected to the network and includes a transmitter and a receiver. The transmitter outputs a signal modulated with outgoing traffic onto the network and the receiver receives a signal from the network modulated with incoming traffic. The station includes a monitoring circuit which introduces a variable delay in a signal from the transmitter and combines the delayed signal with the received signal so as to produce an output dependent upon the correlation of the signal from the transmitter and the received signal at the given delay. Preferably, the network is an optical network and the delay is introduced by a programmable delay line.
摘要翻译： PCT No.PCT / GB92 / 01807 Sec。 371日期：1994年5月24日 102（e）日期1994年5月24日PCT提交1992年10月1日PCT公布。 出版物WO93 / 07687 日期：1993年04月15日。一种用于监测站点连接到网络并包括发射机和接收机的网络的系统。 发射机将输出业务调制的信号输出到网络上，并且接收机从接收到的流量调制的网络接收信号。 该站包括监测电路，其将来自发射机的信号中的可变延迟引入，并将延迟的信号与接收的信号进行组合，以产生取决于来自发射机的信号与给定延迟的接收信号的相关性的输出 。 优选地，网络是光网络，并且延迟由可编程延迟线引入。
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公开(公告)号：US5559625A
公开(公告)日：1996-09-24
申请号：US403744
申请日：1995-04-21
CPC分类号： H04Q11/0003 , H04J14/0291 , H04J14/0297 , H04J14/0282 , H04J14/0286 , H04Q2011/0081 , H04Q2011/0083
摘要： A distributive communications network includes groups of nodes at different levels. Each set of nodes at one level is connected to an associated node in the level above for transmission and reception of traffic. Traffic is assigned to one of a number of bands of wavelengths according to whether it is local or wider area traffic. At the first level of node local area traffic in the corresponding band of wavelengths is looped back and retransmitted to all of the terminals that are connected to that node. At each level of node, traffic is either passed on to a higher level, or looped back according to the band of wavelengths to which it is assigned. Thus, the wavelength band determines the node level at which the traffic is looped back, and the breadth of terminals ultimately exposed to this traffic. It is possible to re-use bands of wavelengths for communicating between terminals.
摘要翻译： PCT No.PCT / GB93 / 01898 Sec。 371日期1995年04月21日 102（e）1995年4月21日PCT PCT 1993年9月8日PCT公布。 出版物WO94 / 07340 日期1994年3月31日分布式通信网络包括不同级别的节点组。 一个级别的每组节点连接到上述级别中的关联节点，以便传输和接收流量。 业务根据是本地还是更广域流量分配给多个波长带中的一个。 在节点的第一级，在相应的波段中的本地区域流量被环回并且重传到连接到该节点的所有终端。 在节点的每个级别，流量或者被传递到更高的级别，或者根据其被分配的波长带环回。 因此，波长带确定业务被环回的节点级别，并且终端的宽度最终暴露于该业务。 可以重新使用波长段来在终端之间进行通信。
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公开(公告)号：US5153764A
公开(公告)日：1992-10-06
申请号：US314761
申请日：1989-02-02
CPC分类号： H04J14/08 , H04B10/50 , H04J3/0682 , H04J14/02
摘要： A method and control system for controlling a signal from each outstation in a multiple access passive optical network including a central node and a plurality of outstations involves monitoring, at the exchange, the value of a parameter of a signal from reach outstation. The value of the parameter is monitored relative to a predetermined discrimination value to detect the signal relative to predetermined first and second reference values defining a range of acceptable values for the parameter. If the value of the parameter for a detected signal falls outside the range, a control signal is transmitted from the node to instruct the relevant outstation to alter the value of the parameter as required to bring the value into the acceptable range for subsequent signals originating from that outstation. The method and system are particularly adapted for controlling the temporal position and the amplitude of outstation signals in a TDM passive optical network. A transceiver for use with such a system is also disclosed.
摘要翻译： PCT No.PCT / GB88 / 00356 Sec。 371日期1989年2月2日 102（e）日期1989年2月2日PCT提交1988年5月6日PCT公布。 公开号WO88 / 09093 日期：1988年11月17日。一种用于控制包括中央节点和多个外站的多址无源光网络中的每个外站的信号的方法和控制系统，包括在交换时监视信号的参数的值 从达到outstation。 相对于预定鉴别值监视参数的值，以相对于定义参数的可接受值的范围的预定的第一和第二参考值来检测信号。 如果检测信号的参数值超出该范围，则从节点发送控制信号，以指示相关外站根据需要改变参数的值，以使该值进入可接受的范围，用于源自 那个外站。 该方法和系统特别适用于控制TDM无源光网络中的外站信号的时间位置和振幅。 还公开了一种用于这种系统的收发器。
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10.发明授权Method of communicating digital signals and receiver for use with such method 失效传播数字信号的方法和采用这种方法的接收机
公开(公告)号：US5144669A
公开(公告)日：1992-09-01
申请号：US348575
申请日：1989-04-28
申请人： David W. Faulkner , Dianne M. Russ
发明人： David W. Faulkner , Dianne M. Russ
CPC分类号： H04J3/08
摘要： A receiver (2) for selectively extracting one of two or more time division multiplexed channels of digital signals, which channel has been scrambled before multiplexing using a predetermined digital sequence comprising: a clock means (4) arranged to provide clock pulses having a repetition rate dependent on a clock control signal; a digital sequence generator (10) triggered by each clock pulse to provide a generator signal representative of the next digit in the predetermined digital sequence; a sampling means (8) arranged to provide a sampled signal at the clock pulse rate; and a phase lock means (8, 18, 25, 26, 22, 4, 10) controlling the clock control signal whereby the generator sequence is delay-lockable to the sampled signal. The receiver finds particular application with the reception of digital video signals broadcast through a passive optical network.
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