公开(公告)号：US5983278A

公开(公告)日：1999-11-09

申请号：US635315

申请日：1996-04-19

申请人： Song Chong ,  Mark Katz ,  David A. Morano ,  Ramesh Nagarajan ,  Walter Michael Pitio ,  Donald D. Shugard ,  Yung-Terng Wang

发明人： Song Chong ,  Mark Katz ,  David A. Morano ,  Ramesh Nagarajan ,  Walter Michael Pitio ,  Donald D. Shugard ,  Yung-Terng Wang

IPC分类号： H04L12/56 ,  H04Q11/04

CPC分类号： H04L49/102 ,  H04L12/5602 ,  H04L2012/5635 ,  H04L2012/5651 ,  H04L2012/5682 ,  H04L49/30

摘要： In a switch fabric environment, which includes a buffer, packet data of different class-types from different sources is received, stored in the buffer, processed and outputted to its intended destination. As the buffer fills up, transmission from some of the data sources is stopped to avoid dropping of packets. To avoid packet loss, when the occupancy of the buffer reaches a first threshold value, further transmission of a first-class type of data is precluded from the particular source of that data then being received, while transmission from other sources of that same first-class type of data is not precluded from these other data sources until first-class type of data from such other sources is also received. Further, data of a second-class type is not precluded from being transmitted as long as the amount of data stored in the buffer remains below a second threshold, which is greater than the first threshold. When the occupancy of the buffer reaches that second threshold, further transmissions from the particular source of that second-class type of data then being received is also precluded. As data from other sources of that second-class type of data is received, further transmissions from those other sources are also precluded. A third-class type of data, however, is not precluded from transmission as long as the amount of data remains below a third threshold value, which is greater than the second threshold value. In order to avoid packet loss, when a packet from any source is received, it is stored regardless of whether transmission from the source of that packet has been precluded. Advantageously, a MAX/MIN distribution of the available bandwidth can be probabilistically achieved without packet loss.

摘要翻译： 在包括缓冲器的交换结构环境中，接收到来自不同源的不同类型的分组数据，存储在缓冲器中，并被处理并输出到其预定目的地。 当缓冲区填满时，一些数据源的传输被停止，以避免丢包。 为了避免分组丢失，当缓冲器的占用达到第一阈值时，从该数据的特定源排除第一类数据的进一步传输，然后被接收，同时从相同的第一阈值的其他源的传输， 直到来自这些其他来源的一流数据类型也被接收到，类型的数据不会从这些其他数据源中排除。 此外，只要存储在缓冲器中的数据量保持低于大于第一阈值的第二阈值，则不排除第二类类型的数据的发送。 当缓冲器的占用达到第二阈值时，也排除了从接收到的该二级类型的数据的特定源的进一步传输。 当接收到来自该二类数据类型的其他来源的数据时，也排除了来自其他来源的进一步传输。 然而，只要数据量保持低于大于第二阈值的第三阈值，则不排除第三类数据的传输。 为了避免分组丢失，当接收到来自任何源的分组时，无论从该分组的源的传输是否被排除，都被存储。 有利地，可以概率地实现可用带宽的MAX / MIN分布，而没有分组丢失。

公开(公告)号：US5834980A

公开(公告)日：1998-11-10

申请号：US268752

申请日：1994-06-30

申请人： Walter M. Pitio ,  Donald D. Shugard

发明人： Walter M. Pitio ,  Donald D. Shugard

IPC分类号： H03L7/06 ,  H04L7/033 ,  H04L7/08 ,  H03L7/07

CPC分类号： H04L7/033

摘要： A method and apparatus for recovering the time base of signals which change at periodic intervals is disclosed. The apparatus comprises gated voltage controlled oscillators (GVCO) that are alternated or exchanged, to reduce phase and frequency deviations in the recovered time base signal, such as the deviations induced by inherent GVCO differences. Each GVCO is stabilized by a respective phase locked loop. The respective GVCOs are gated only in response to a chosen polarity transition in the input signal, to make the circuit more tolerant of waveform distortions. More than two GVCOs may be used to provide improved frequency drift resistance. The circuit uses resynchronization control signals, such as the time slot signal in synchronous switching systems, to indicate resynchronization or reassignment of the GVCOs in gaps in the data transmission. Automatic reassignment is insured when there are periods of non-transitioning data that last longer than the stability of the GVCOs to prevent frequency drift in the recovered clock.

摘要翻译： 公开了一种用于恢复以周期性间隔变化的信号的时基的方法和装置。 该装置包括交替或交换的门控电压控制振荡器（GVCO），以减少恢复的时基信号中的相位和频率偏差，例如由固有GVCO差引起的偏差。 每个GVCO由相应的锁相环稳定。 相应的GVCO仅在响应于输入信号中选择的极性转变时选通，以使电路更容忍波形失真。 可以使用两个以上的GVCO来提供改进的耐频漂性。 该电路使用同步控制信号，例如同步交换系统中的时隙信号来指示GVCO在数据传输中的间隙中的再同步或重新分配。 当存在持续比GVCO的稳定性更长的非转换数据的周期以防止恢复的时钟中的频率漂移时，自动重新分配被保险。

公开(公告)号：US5317658A

公开(公告)日：1994-05-31

申请号：US864293

申请日：1992-04-06

申请人： Glenn D. Bergland ,  John V. Camlet ,  Saul J. Einbinder ,  Walter M. Pitio ,  Robert C. Pritchard ,  George J. Shevchuk ,  Donald D. Shugard

发明人： Glenn D. Bergland ,  John V. Camlet ,  Saul J. Einbinder ,  Walter M. Pitio ,  Robert C. Pritchard ,  George J. Shevchuk ,  Donald D. Shugard

IPC分类号： G02B6/34 ,  G02B6/35 ,  G02B6/26

CPC分类号： G02B6/2773 ,  G02B6/272 ,  G02B6/3546 ,  G02B6/3592

摘要： An apparatus and method are disclosed for implementing a polarization-independent optical switch wherein switchable communication signals are retained in the optical mode while being switched between optical links in an optical communication network. The polarization-independent optical switch comprises polarization-dependent components which are advantageously arranged to switch arbitrary polarized light waves. The polarization-independent optical switch is achieved by splitting incoming arbitrary polarized light waves into two paths, a light wave with a TE radiation component and a light wave with a TM radiation component. The light wave with the TE radiation component is converted to a light wave with a TM radiation component. Both light waves having the TM radiation component are then switched in a polarization-dependent photonic switch device. The arbitrary light waves are recovered from the optical switch by converting one of the switched light waves having the TM radiation component to a light wave having the TE radiation component. The light wave with this TE radiation component is combined with the remaining switched light wave having the TM radiation component in a polarization combiner. As the polarization of the input light waves vary, more or less of the light wave energy will pass through the first path of the optical switch or the second path of the optical switch. The total amount of light wave energy through the optical switch, however, will remain relative constant.

摘要翻译： 公开了一种用于实现偏振无关光学开关的装置和方法，其中可切换通信信号在光学模式下被保持，同时在光通信网络中的光链路之间切换。 偏振无关光学开关包括偏振相关分量，其有利地布置成切换任意偏振光波。 偏振无关的光开关通过将入射的任意偏振光波分成两个路径，具有TE辐射分量的光波和具有TM辐射分量的光波来实现。 具有TE辐射分量的光波被转换成具有TM辐射分量的光波。 然后，在偏振相关的光子开关装置中切换具有TM辐射分量的两个光波。 通过将具有TM辐射分量的切换光之一转换成具有TE辐射分量的光波，从光开关中恢复任意的光波。 具有该TE辐射分量的光波与在偏振组合器中具有TM辐射分量的剩余切换光波组合。 随着输入光波的偏振变化，或多或少的光波能量将通过光开关的第一路径或光开关的第二路径。 然而，通过光学开关的光波能量的总量将保持相对恒定。