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公开(公告)号：US5187610A
公开(公告)日：1993-02-16
申请号：US810273
申请日：1991-12-19
IPC分类号： G02F1/35 , H01S3/06 , H01S3/067 , H01S3/07 , H01S3/094 , H01S3/10 , H01S3/23 , H04B10/16 , H04B10/17
CPC分类号： H01S3/06754 , H01S3/06758 , H01S2301/02
摘要： In an optical arrangement for amplifying an input lightwave signal by a predetermined amount to a desired output level, an optical amplifier is connected to a loss element. The optical amplifier is pumped by an amount exceeding a nominal amount wherein the nominal amount is the amount of pumping needed to attain the desired output level at the optical amplifier output. By attenuating the signal output from the optical amplifier, the loss element generates an output signal from the optical arrangement at the desired output level. This optical arrangement is characterized by an improved noise performance (noise figure) over standard optical amplifiers.
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公开(公告)号：US5091916A
公开(公告)日：1992-02-25
申请号：US590201
申请日：1990-09-28
IPC分类号： H01S3/07 , H01S3/067 , H01S3/08 , H01S5/00 , H01S5/026 , H01S5/0625 , H01S5/12 , H01S5/125 , H01S5/14
CPC分类号： H01S5/125 , H01S3/067 , H01S5/06256 , H01S5/0654 , H01S5/1206 , H01S5/1212 , H01S5/1215 , H01S5/146
摘要： Improved side mode suppression with significantly reduced side mode suppression ratio fluctuation during laser tuning is realized in a distributed Bragg reflector laser structure by incorporating at least one reflector element which exhibits an asymmetric reflection characteristic versus wavelength over a band of wavelengths wide enough to include at least two longitudinal modes of the laser. That is, the asymmetric characteristic is wider than the mode separation for adjacent longitudinal modes of the laser. In one embodiment, a distributed Bragg reflector laser is shown wherein the Bragg reflector includes a corrugated waveguides with corrugations having a period which varies nonlinearly from .LAMBDA..sub.O at one end of the reflector to .LAMBDA.hd L at the opposite end of the reflector, where .LAMBDA..sub.O is greater than .LAMBDA..sub.L. Integrated and extended cavity or hybrid structures are described in both semiconductor and fiber laser structures.
摘要翻译： 通过在分布式布拉格反射器激光器结构中实现改进的侧面模式抑制，在分布式布拉格反射器激光器结构中实现了具有非对称反射特性对波长的至少一个反射器元件的侧面模式抑制，波长宽度足以至少包括 激光的两种纵向模式。 也就是说，不对称特性比激光的相邻纵向模式的模式分离宽。 在一个实施例中，示出了分布布拉格反射器激光器，其中布拉格反射器包括具有波纹的波纹波导，波纹具有在反射器的一端处的LAMBDA O非线性地变化到在反射器的相对端处的LAMBDA hd L的周期，其中LAMBDA O大于LAMBDA L.在半导体和光纤激光器结构中都描述了集成和扩展腔或混合结构。
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3.发明授权
公开(公告)号：US4797879A
公开(公告)日：1989-01-10
申请号：US58739
申请日：1987-06-05
CPC分类号： H04L12/413 , H04J14/0227 , H04J14/0241 , H04L12/44 , H04L12/56 , H04Q11/0062 , H04J14/0282 , H04Q11/0066 , H04Q2011/0041 , H04Q2011/0094
摘要： The present invention relates to packet switched interconnection protocols for use in high-speed optical Star-configured Local Area Networks (LANs). In the present Star LAN, a plurality of N+1 wavelength division multiplexed (WDM) channels are provided for use by M transceivers connected to the Star coupler, where preferably M>N. N of the N+1 WDM channels are used for transmission of data packets, and the remaining WDM channel is used by all transceivers for transmitting control packets only. In the present protocols, a transmitter in an active transceiver first send a control packet over the control channel using a first protocol such as, for example, ALOHA or CSMA. The control packet includes (1) the transmitter's unique address, (2) the destined receiver's address, and (3) the address of the data channel to be used in transmitting the associated data packet. Immediately after the control packet is sent, the associated data packet is transmitted over the chosen one of the N data channels using a second protocol such as, for example, ALOHA, CSMA or N-Server Switch. In the Star network, the transceivers receive their own transmissions and detect if a collision or not has occurred, and if a collision is detected the transmission procedure is repeated until successful.
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公开(公告)号：US5946360A
公开(公告)日：1999-08-31
申请号：US826416
申请日：1997-03-27
申请人： Isam M. I. Habbab , Sanjay Kasturia
发明人： Isam M. I. Habbab , Sanjay Kasturia
IPC分类号： H04L27/22 , H04L7/04 , H04L27/00 , H04L27/233
CPC分类号： H04L27/2332 , H04L2027/003 , H04L2027/0057 , H04L2027/0069 , H04L2027/0073 , H04L2027/0093 , H04L7/046
摘要： The along and perpendicular rails of a received signal (e.g., modulated using multi-phase shift keying) are rotated to compensate for frequency offsets between the carrier frequency of the received signal and the reference frequency of the local oscillator. The rotation angles are updated, based on the rotated along rail, during dotting sequences in the received signal. In one implementation, the dotting sequences are detected based on the rotated perpendicular rail. The beginnings of dotting sequences are detected by thresholding the average on the perpendicular rail, and the ends of dotting sequences are detected by analyzing the encoded data for non-dotting-sequence values. In a cordless phone application, different dotting sequences may be used to distinguish base-to-handset transmissions from handset-to-base transmissions.
摘要翻译： 接收信号的沿着和垂直的轨道（例如，使用多相位移相键调制）被旋转以补偿接收信号的载波频率和本地振荡器的参考频率之间的频率偏移。 在接收到的信号中的点划线期间，旋转角度基于沿轨道的旋转更新。 在一个实现中，基于旋转的垂直轨迹来检测点划线。 通过对垂直轨道上的平均值进行阈值来检测点序列的开始，通过分析非点数序列值的编码数据来检测点序列的末端。 在无绳电话应用中，可以使用不同的点序列来区分基站到手机的传输与手机到基站的传输。
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公开(公告)号：US5022730A
公开(公告)日：1991-06-11
申请号：US449040
申请日：1989-12-12
CPC分类号： G02F1/225
摘要： A wavelength tunable optical filter having a characteristic single transmission peak for enhanced tunability comprises a phase control section positioned between a Distributed Bragg Reflector section and a high reflectivity mirror. The Distributed Bragg Reflector section comprises a periodic region grating positioned over an end portion of a passive waveguide whereas the phase control section comprises the portion of the passive waveguide region located between the grating and the mirror. Continuous tunability in the range of several THz may be achieved by controlling the refractive index in either the phase control or distributed Bragg reflector section. The optical filter is expected to have a frequency switching time of a few nanoseconds and, thus, is applicable to both transmission and switching applications.
摘要翻译： 具有用于增强可调性的特征性单传输峰值的波长可调光滤波器包括位于分布式布拉格反射器部分和高反射镜之间的相位控制部分。 分布布拉格反射器部分包括位于无源波导的端部上的周期性区域光栅，而相位控制部分包括位于光栅和反射镜之间的无源波导区域的部分。 在几个THz的范围内的连续可调性可以通过控制相位控制或分布式布拉格反射器部分中的折射率来实现。 光滤波器预计具有几纳秒的频率切换时间，因此适用于传输和切换应用。
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公开(公告)号：US5008958A
公开(公告)日：1991-04-16
申请号：US308697
申请日：1989-02-08
IPC分类号： H04B10/135
CPC分类号： H04B10/532
摘要： To exploit the potential advantages of coherent optical communications systems, the polarization states of the received optical signal and the local oscillator waves must be matched. A mismatch may severely degrade detection performance. These mismatches occur because the received signal state of polarization changes with time and along the fiber. We first review several existing techniques for handling this problem, such as polarization-maintaining fibers, polarization-state controllers and polarization-diversity receivers. The insensitive technique reduces the problem of polarization mismatch by forcing the polarization state of either the transmitted signal or local oscillator to vary with time in a non-adaptive manner so that polarization-insensitive performance is obtained. The proposed scheme adopts a completely new approach which uses high-birefringence single-mode fibers to implement polarization switching. These techniques require only a single photodetector and give a fixed level of detection performance, with a power penalty relative to ideal of 3 dB. A specific technique is presented in which polarization-insensitive heterodyne detection is achieved through data-induced polarization switching. The polarization switching is brought about by inserting a passive, birefringent optical device in the path of the transmitted FSK signal.
摘要翻译： 为了利用相干光通信系统的潜在优势，必须匹配接收的光信号和本地振荡器波的极化状态。 不匹配可能严重降低检测性能。 发生这些不匹配是因为接收到的信号状态的偏振随时间和光纤而变化。 我们首先回顾了现有的几种处理这个问题的技术，例如偏振维持光纤，极化状态控制器和极化分集接收器。 不灵敏技术通过强制发射信号或本地振荡器的偏振状态以非自适应方式随时间变化来减少偏振失配的问题，从而获得极化不敏感的性能。 该方案采用高双折射单模光纤实现偏振切换的全新方法。 这些技术仅需要一个光电检测器，并提供固定的检测性能水平，相对于理想的3dB的功率损失。 提出了通过数据激励极化切换实现极化不敏感外差检测的具体技术。 通过在被发送的FSK信号的路径中插入无源双折射光学器件来实现偏振切换。
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