Locating system and method
    1.
    发明授权
    Locating system and method 失效
    定位系统及方法

    公开(公告)号:US4812852A

    公开(公告)日:1989-03-14

    申请号:US16788

    申请日:1987-02-20

    CPC分类号: G01S5/021 G01S5/0009 G01S5/06

    摘要: The present invention includes both a system and a method for locating a source of a randomly modulated radio signal. In one form of the invention, at least three receiving stations at known locations receive and process the randomly modulated radio signal. A common reference level is selected for the radio signal at each of the receiving stations. The times of arrival at each receiving station of selected transitions of the radio signal with reference to the common reference level are determined. Each receiving station provides an indication of the times of arrival of the selected transitions to a central facility for processing to provide an indication of the location of the signal source.

    摘要翻译: 本发明包括用于定位随机调制的无线电信号的源的系统和方法。 在本发明的一种形式中,已知位置处的至少三个接收站接收和处理随机调制的无线电信号。 在每个接收站处为无线电信号选择公共参考电平。 参考公共参考电平确定无线电信号的选定转换的每个接收站的到达时间。 每个接收站向所述中央设备提供所选转场的到达时间的指示以进行处理以提供信号源的位置的指示。

    Injection laser diode digital transmitter having signal quality
monitoring arrangement
    2.
    发明授权
    Injection laser diode digital transmitter having signal quality monitoring arrangement 失效
    注射激光二极管数字发射器具有信号质量监测装置

    公开(公告)号:US4307469A

    公开(公告)日:1981-12-22

    申请号:US141590

    申请日:1980-04-18

    摘要: An injection laser diode transmitter for a fiber optic link contains a detector that monitors transmitted optical pulses for signal quality. The transmitted signal component is extracted from the back facet of the ILD for feedback stability control and is coupled to signal quality measuring circuitry from a wideband current-to-voltage converter that is coupled to the output of a fast photo diode that extracts the optical output signal from the rear facet of the ILD for the purposes of generating a feedback control voltage to be used for ILD bias control. The bias current feeds a reference amplifier, the output of which is coupled to a lowpass filter to remove the pulse signal component. The output of the lowpass filter is a DC voltage level which is proportional to the average optical output of the ILD. The voltage level output of the lowpass filter is applied to a current sink coupled to the ILD. The bias current for the ILD is controlled to drive the differential to zero. Because the bias current control feedback loop is responsive to the optical output of the ILD, the bias current is automatically compensated for changes in temperature.The current-to-voltage converter output is further coupled to a buffer amplifier to supply an output voltage to downlink signal quality monitoring circuitry to facilitate fault isolation.

    摘要翻译: 用于光纤链路的注入激光二极管发射器包含检测器,用于监视传输的光脉冲以获得信号质量。 所发射的信号分量从ILD的后面提取用于反馈稳定性控制,并且耦合到来自宽带电流 - 电压转换器的信号质量测量电路,所述宽带电流 - 电压转换器耦合到提取光输出的快速光电二极管的输出 来自ILD的后面的信号,用于产生用于ILD偏置控制的反馈控制电压。 偏置电流馈送参考放大器,其参考放大器耦合到低通滤波器以去除脉冲信号分量。 低通滤波器的输出是与ILD的平均光输出成比例的直流电压电平。 低通滤波器的电压电平输出被施加到耦合到ILD的电流宿。 控制ILD的偏置电流以将差分驱动到零。 由于偏置电流控制反馈回路响应于ILD的光输出,所以偏置电流自动补偿温度变化。 电流 - 电压转换器输出进一步耦合到缓冲放大器以向下行链路信号质量监视电路提供输出电压以便于故障隔离。

    Bit rate-insensitive mechanism for transmitting integrated clock and
data signals over digital communication link
    3.
    发明授权
    Bit rate-insensitive mechanism for transmitting integrated clock and data signals over digital communication link 失效
    通过数字通信链路传输集成时钟和数据信号的比特率不灵敏机制

    公开(公告)号:US5550864A

    公开(公告)日:1996-08-27

    申请号:US160054

    申请日:1993-12-01

    IPC分类号: H04L25/49

    CPC分类号: H04L25/4904

    摘要: A totally D.C. balanced and bit-rate independent digital clock encoding technique is applicable to a variety of digital signalling systems, including fiber optic digital signalling. Each of successive event cells of the clock signal is demarcated by clock transitions of opposite polarity, so that each clock cycle contains two event cells, one of which is redundant. For a first binary data value, such as a `0`, a pair of unmodified successive event cells of the clock signal are provided as an output. Namely, the clock signal is unaffected, so that both halves of a complete, unmodified clock cycle are reproduced `as is` as the encoded clock output. For a second binary data value, such as a `1`, an event cell is modified by inserting a pulse, of finite duration, less than the duration of the event cell, the pulse being delayed with respect to a leading clock transition of the pair of alternating, opposite clock transitions of the event cell. Since event cells are encoded in pairs, in order to provide redundancy and achieve total D.C. balance, the first pulse has a first polarity, while the second pulse has a second, complementary polarity. Because the encoding mechanism of the present invention has built-in redundancy, it readily accommodates both quality monitoring at the receiver, as well as sub-rate channel signalling.

    摘要翻译: 一个完整的直流平衡和比特率独立数字时钟编码技术适用于各种数字信号系统,包括光纤数字信号。 时钟信号的每个连续事件单元被相反极性的时钟转换划分,使得每个时钟周期包含两个事件单元,其中之一是冗余的。 对于诸如“0”的第一二进制数据值,提供时钟信号的一对未修改的连续事件单元作为输出。 也就是说,时钟信号不受影响,使得完整的未修改的时钟周期的两半被再现为“编码时钟输出”。 对于诸如“1”的第二二进制数据值,通过插入小于事件单元的持续时间的有限持续时间的脉冲来修改事件单元,所述脉冲相对于所述事件单元的前导时钟转换被延迟 一对事件单元的交替的,相反的时钟转换。 由于事件单元被成对编码,为了提供冗余并实现总的直流平衡,第一脉冲具有第一极性,而第二脉冲具有第二互补极性。 因为本发明的编码机制具有内置的冗余性,所以它容易地适应接收机的质量监测以及子速率信道信令。

    Fiber optic telecommunication system employing continuous downlink,
burst uplink transmission format with preset uplink guard band
    4.
    发明授权
    Fiber optic telecommunication system employing continuous downlink, burst uplink transmission format with preset uplink guard band 失效
    采用连续下行链路的光纤电信系统,具有预设上行卫星频带的突发上行传输格式

    公开(公告)号:US5457560A

    公开(公告)日:1995-10-10

    申请号:US243193

    申请日:1994-05-16

    摘要: A fiber optic telecommunication system has master site linked to a plurality of subscriber interface sites by a single pair of optical fibers. Downlink messages are transmitted in a continuous TDM format over a first optical fiber from the master site to subscriber interface sites, and in a burst mode TDMA format over a second optical fiber from the subscriber interface sites to the master site. Each subscriber interface site is coupled to the optical fiber link by way of a multiple fan-out fiber coupling pedestal at a common location on the fiber pair. To prevent collisions between successive uplink bursts from the subscriber interface sites, a guard band separates successive uplink messages from one another. The guard band duration accommodates optical fiber transmission distance between the common location on the uplink optical fiber and the subscriber interface site whose differential optical fiber transmission distance from the common location is greatest. A subscriber location has a television decoder associated with the subscriber's television set, through which television channel selection signals are input by the subscriber for transmission from the subscriber interface site to the master site. Power is provided by way of a replaceable battery pack, housed in a subterrestrial bell jar configuration, effectively insulating the battery pack from extreme temperature changes and the intrusion of moisture.

    摘要翻译: 光纤电信系统具有通过一对光纤链接到多个用户接口站点的主站点。 下行链路消息以连续的TDM格式通过第一光纤从主站点到用户接口站点以第二光纤从用户接口站点到主站点以突发模式TDMA格式发送。 每个用户接口站点通过在光纤对上的公共位置处的多扇出光纤耦合基座耦合到光纤链路。 为了防止来自订户接口站点的连续上行链路突发之间的冲突,保护带将相继的上行链路消息彼此分离。 保护频段持续时间适应上行光纤上的公共位置与与公共位置的差分光纤传输距离最大的用户接口位置之间的光纤传输距离。 用户位置具有与用户电视机相关联的电视解码器,通过该电视解码器,用户输入电视频道选择信号以从用户接口站点传送到主站点。 电源通过可更换的电池组提供,容纳在地下钟罩配置中,有效地使电池组绝缘不受极端温度变化和潮湿侵入。

    System for lightning ground stroke position by time of arrival
discrimination
    5.
    发明授权
    System for lightning ground stroke position by time of arrival discrimination 失效
    雷达接地冲击位置系统由到达时间辨认

    公开(公告)号:US4543580A

    公开(公告)日:1985-09-24

    申请号:US339789

    申请日:1982-01-15

    CPC分类号: G01S1/24 G01S5/02

    摘要: A lightning ground stroke location system employs a time-of-arrival discrimination scheme which uses, as its time synchronization base, the U.S. Coast Guard LORAN-C navigation network. The system comprises a plurality (at least three and preferably four) of geographically separated lightning stroke monitoring stations. Each station contains a lightning stroke detector and a timing signal generator that is synchronized with the timing signal generator at each other respective detection location. The timing signal generation equipment at each receiver is comprised of a LORAN-C signalling responsive receiver which monitors the same encoded signal group emitted from a common LORAN-C reverence source. Each of the ground stroke detection stations is further connected via a respective communication link to a central processing facility.When a ground stroke occurs, the electromagnetic pulse emitted is detected by each listening station, which records the time of detection of the ground stroke by sampling an internal synchronized clock at that particular station so as to record the time that the stroke was detected relative to the standard timing cycle is emitted by the reference Coast Guard station source. This time data is then transmitted to the central processing station, which after compensating for relative LORAN time signal propagation delay calculates the stroke location.

    摘要翻译: 闪电地面冲击定位系统采用到达时间鉴别方案,其使用美国海岸警卫队LORAN-C导航网络作为其时间同步基准。 该系统包括多个(至少三个,优选四个)地理上分离的雷击监测站。 每个站包括雷击探测器和定时信号发生器,其与定时信号发生器在彼此相应的检测位置同步。 每个接收机的定时信号产生设备由LORAN-C信令响应接收机组成,监听从普通的LORAN-C尊敬源发射的相同的编码信号组。 每个地面行程检测站通过相应的通信链路进一步连接到中央处理设施。 当发生接地冲击时,发出的电磁脉冲由每个监听站检测,每个监听站通过在该特定站采样内部同步时钟来记录地面行程的检测时间,以记录相对于 标准时序周期由参考海岸警卫队站源发出。 然后将该时间数据发送到中央处理站,其在补偿相对LORAN时间信号传播延迟之后计算行程位置。

    Temperature compensated avalanche photodiode optical receiver circuit
    6.
    发明授权
    Temperature compensated avalanche photodiode optical receiver circuit 失效
    温度补偿雪崩光电二极管光接收电路

    公开(公告)号:US4438348A

    公开(公告)日:1984-03-20

    申请号:US949231

    申请日:1978-10-06

    IPC分类号: H04B10/158 H03K3/42 H01J7/24

    CPC分类号: H04B10/6911

    摘要: A photodiode receiver circuit having self-contained automatic gain control and which is temperature compensated over a wide operating range contains a resistor coupled in series between a bias power supply and one end of an avalanche photodiode. Self-generated AGC action results from the fact that the gain of an avalanche photodiode increases as the bias voltage applied across the diode increases. As the light intensity received by the diode increases, there is a corresponding increase in the current flow through the diode and the series-connected resistor. The consequential increase in IR drop across the resistor decreases the bias voltage across the diode, so that the gain of the diode is reduced. Through this action, the dynamic range of optical input of the photodiode will be increased for a fixed dynamic range of electrical output.Temperature compensation is achieved by coupling a temperature-sensitive voltage divider circuit between the bias voltage supply and the gain-controlling resistor. This voltage divider network may include a thermistor coupled in parallel with one resistor component of a resistor divider that is connected to a bias voltage source. The value of the parallel resistor is chosen to match the thermistor's characteristic to the voltage versus temperature characteristic of the APD so that a temperature-compensated bias voltage reference, to which the gain-controlling resistor is connected, is available over a wide temperature range (e.g. -40.degree. C. to +60.degree. C.). This temperature compensation allows the avalanche photodiode to be operated at a nearly constant available gain across this range and prevents the diode from being damaged by too high a bias voltage.

    摘要翻译: 具有独立自动增益控制并且在宽工作范围内进行温度补偿的光电二极管接收器电路包含串联耦合在偏置电源和雪崩光电二极管的一端之间的电阻器。 自发生的AGC动作是由于雪崩光电二极管的偏置电压增加而增加的。 随着二极管接收的光强增加,通过二极管和串联电阻的电流相应增加。 因此,电阻上的IR降低会降低二极管两端的偏置电压,从而降低二极管的增益。 通过这种动作,光电二极管的光输入的动态范围将在电输出的固定动态范围内增加。 通过将偏置电压源和增益控制电阻之间的温度敏感分压器电路耦合来实现温度补偿。 该分压器网络可以包括与连接到偏置电压源的电阻分压器的一个电阻器部件并联耦合的热敏电阻。 选择并联电阻的值以匹配热敏电阻的特性与APD的电压对温度特性,使得增益控制电阻连接到的温度补偿偏置电压参考在宽温度范围内可用( 例如-40℃至+ 60℃)。 这种温度补偿允许雪崩光电二极管在这个范围内以几乎恒定的可用增益运行,并且防止二极管被太高的偏置电压损坏。

    Clock extractor for high speed, variable data rate communication system
    7.
    发明授权
    Clock extractor for high speed, variable data rate communication system 失效
    时钟提取器,用于高速,可变数据速率通信系统

    公开(公告)号:US5963608A

    公开(公告)日:1999-10-05

    申请号:US882923

    申请日:1997-06-26

    摘要: To derive a clock embedded in a digital data stream, a variable data rate synchronizer includes a data rate estimator that derives an estimate of the data rate of data contained in the digital data signal, and a frequency estimator that derives an estimate of the frequency of the output of a voltage controlled oscillator. A phase lock loop includes a phase detector to which the digital data signal and the output of the voltage controlled oscillator are coupled and has an output coupled to a sweepable loop filter. The output of the loop filter is coupled to the voltage controlled oscillator. During an initital frequency acquisition mode, the sweep controller sequentially varies an analog voltage applied to the voltage controlled oscillator, until the estimate of the data rate effectively corresponds to the estimate of the frequency of the output of the voltage controlled oscillator. This terminates the frequency acquisition mode and initiates a phase acquisition mode, during which the sweep controller causes a sawtooth sweep of the loop filter, until the output of the loop filter corresponds to the actual frequency of said embedded clock signal, thereby locking the loop to the embedded clock.

    摘要翻译: 为了导出嵌入在数字数据流中的时钟,可变数据速率同步器包括导出数字数据信号中包含的数据的数据速率的估计的数据速率估计器,以及频率估计器, 压控振荡器的输出。 锁相环包括相位检测器,数字数据信号和压控振荡器的输出耦合到该相位检测器,并具有耦合到可扫描环路滤波器的输出。 环路滤波器的输出耦合到压控振荡器。 在初始频率获取模式期间,扫描控制器顺序地改变施加到压控振荡器的模拟电压,直到数据速率的估计对应于压控振荡器的输出频率的估计。 这终止了频率获取模式,并且启动相位采集模式,在此期间,扫描控制器引起环路滤波器的锯齿波扫描,直到环路滤波器的输出对应于所述嵌入式时钟信号的实际频率,由此锁定环路 嵌入式时钟。

    Method and apparatus for extracting an embedded clock from a digital
data signal
    8.
    发明授权
    Method and apparatus for extracting an embedded clock from a digital data signal 失效
    从数字数据信号中提取嵌入式时钟的方法和装置

    公开(公告)号:US5838749A

    公开(公告)日:1998-11-17

    申请号:US462168

    申请日:1995-06-05

    摘要: A data and clock recovery arrangement, for a high speed fiber optic digital communication system in which a serial digital bit stream is pre-scramble encoded by interleaving complementary pairs of overhead bits between successive groups of data bits, and then scrambled and transmitted to a receive site, comprises a data rate independent variable bit rate synchronizer, a descrambler and a decoder. The data rate independent variable bit synchronizer processes the received scrambled and encoded digital bit stream to derive a variable data rate synchronization clock signal. The synchronizer is capable of accepting any data rate within the operational data clock signal range of the system, and automatically tunes itself to the data clock signal embedded in the received scrambled and encoded serial data stream, so as to output respective scrambled and encoded serial data and clock signals. The descrambler descrambles the scrambled and encoded serial digital bit stream using the variable data rate synchronization clock signal, and the decoder decodes the descrambled serial digital bit stream to extract groups of data bits exclusive of the complementary pairs of overhead bits and to derive an output clock signal having a frequency coincident with the data rate of the data bits.

    摘要翻译: 一种用于高速光纤数字通信系统的数据和时钟恢复装置,其中串行数字比特流通过在连续的数据比特组之间交织开销比特的互补对进行加密编码,然后被加扰并发送到接收 包括数据速率独立的可变比特率同步器,解扰器和解码器。 数据速率独立的可变位同步器处理接收的加密和编码的数字比特流以导出可变数据速率同步时钟信号。 同步器能够接受系统的运行数据时钟信号范围内的任何数据速率,并自动调谐到嵌入在接收的经加扰和编码的串行数据流中的数据时钟信号,以输出相应的加扰和编码串行数据 和时钟信号。 解扰器使用可变数据速率同步时钟信号对加扰和编码的串行数字比特流进行解扰,并且解码器解码解扰的串行数字比特流以提取不同于开销比特的互补对的数据比特组,并且导出输出时钟 信号具有与数据位的数据速率一致的频率。

    Compensation for variations in temperature and aging of laser diode by
use of small signal, square-law portion of transfer function of diode
detection circuit
    9.
    发明授权
    Compensation for variations in temperature and aging of laser diode by use of small signal, square-law portion of transfer function of diode detection circuit 失效
    通过使用小信号,二次检测电路的传递函数的平方律来补偿激光二极管的温度和老化变化

    公开(公告)号:US5754577A

    公开(公告)日:1998-05-19

    申请号:US685440

    申请日:1996-07-23

    IPC分类号: H01S5/0683 H01S3/103

    CPC分类号: H01S5/0683 H01S5/06832

    摘要: A modulation drive current control loop for a digitally modulated laser diode uses the small signal, square-law portion of an RF signal diode detection circuit to adjust the magnitude of laser modulation drive current, and compensate for variations in temperature and aging of the laser diode. Operating the RF signal detector diode as a non-switched device, in its square-law region, provides several advantages over large signal, switched, linear region devices. When a detector diode is operated in the large signal, switched, linear region, its output depends upon the reduced slope beyond the `knee` region of the curve, so that the diode functions essentially as a switch. In such a large signal detection mode, the diode conducts during only a portion of the input cycle, with its output voltage following peaks of the input signal waveform in accordance with a linear relationship between input voltage and output voltage. This requirement for both a large valued input signal (to overcome the bandgap voltage of the diode) and the need to switch the detector diode on and off necessarily prevents its use with precision at very high (e.g., gigabit) data rates. In contrast therewith, the small signal, square-low detector diode of the present invention can easily produce a proportional output voltage at gigabit speeds using a very small amplitude input signal.

    摘要翻译: 用于数字调制的激光二极管的调制驱动电流控制环路使用RF信号二极管检测电路的小信号,平方律部分来调整激光调制驱动电流的大小,并补偿激光二极管的温度和老化的变化 。 在其平方律区域中操作RF信号检测器二极管作为非开关器件,与大信号,开关,线性区域器件相比提供了几个优点。 当检测器二极管在大信号切换的线性区域中工作时,其输出取决于曲线的“拐点”区域之后的斜率减小,因此二极管基本上起着开关的作用。 在这样大的信号检测模式下,二极管仅在输入周期的一部分期间导通,其输出电压按照输入电压和输出电压之间的线性关系跟随输入信号波形的峰值。 对于大值输入信号(克服二极管的带隙电压)和需要将检测器二极管打开和关闭的需要,必须防止在非常高(例如千兆位)数据速率下的精确使用。 相比之下,本发明的小信号,方形低检测器二极管可以使用非常小的振幅输入信号容易地以千兆位速度产生比例输出电压。

    Locating system and method
    10.
    发明授权
    Locating system and method 失效
    定位系统及方法

    公开(公告)号:US4916455A

    公开(公告)日:1990-04-10

    申请号:US294736

    申请日:1989-01-06

    CPC分类号: G01S5/021 G01S5/0009 G01S5/06

    摘要: The present invention includes both a system and a method for locating a source of a randomly modulated signals. In one form of the invention at least three receiving stations receive and process the randomly modulated signal. A common reference level is selected at each of the receiving stations. The times of arrival at each receiving station of the selected transitions of the signal with reference to the common reference level are determined. Each of the receiving stations provides an indication of the selected transitions to a center facility for processing to provide an indication of the location of the signal.

    摘要翻译: 本发明包括用于定位随机调制信号的源的系统和方法。 在本发明的一种形式中,至少三个接收站接收和处理随机调制的信号。 在每个接收站选择公共参考电平。 参考公共参考水平确定信号的所选转换的每个接收站的到达时间。 每个接收站向所述中心设施提供所选转场的指示,以进行处理以提供信号位置的指示。