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31. 发明申请

WO1997027642A1 ANTENNA FOR FREQUENCIES IN EXCESS OF 200 MHz 审中-公开
标题翻译：天线超过200 MHz的频率
公开(公告)号：WO1997027642A1
公开(公告)日：1997-07-31
申请号：PCT/GB1997000085
申请日：1997-01-10
申请人： SYMMETRICOM, INC. , LEISTEN, Oliver, Paul
发明人： SYMMETRICOM, INC.
IPC分类号： H01Q01/38
CPC分类号： H01Q11/08
摘要： A miniature antenna (10) for operation at frequencies in excess of 200 MHz has a ceramic core (12) in the form of a cylindrical rod having a relative dielectric constant greater than 5. Plated on the outer surfaces of the core is an antenna element structure comprising a single pair of oppositely disposed helical elements (10A, 10B) having a common central axis coincident with the central axis of the core. At a distal end of the antenna, they are connected to a coaxial feeder structure passing axially through the core, and at their proximal ends they are connected to the rim of a cylindrical trap conductor (20) which, at the proximal end of the core is coupled to the screen of the feeder structure. At the operating frequency, the antenna behaves as a loop, the radiation response having nulls directed generally perpendicularly on each side of a plane containing the central axis of the core and the connections of the helical elements with the feeder structure and with the conductive sleeve. The antenna is intended primarily for a handheld communication unit such as a cellular or cordless telephone handset, the present of the nulls in the radiation pattern reducing radiation into the user's head.
摘要翻译：用于在超过200MHz的频率下操作的微型天线（10）具有呈圆柱形棒形式的陶瓷芯（12），其具有大于5的相对介电常数。在芯的外表面上形成天线元件结构包括具有与芯的中心轴重合的公共中心轴线的单对相对设置的螺旋元件（10A，10B）。在天线的远端处，它们连接到轴向穿过芯部的同轴馈送结构，并且在它们的近端处，它们连接到圆柱形陷阱导体（20）的边缘，圆柱形陷阱导体在芯的近端处耦合到馈线结构的屏幕。在工作频率下，天线表现为一个环路，辐射响应的空值大致垂直地指向包含芯的中心轴的平面的每一侧，以及螺旋元件与馈线结构和导电套管的连接。该天线主要用于诸如蜂窝或无绳电话手机的手持通信单元，辐射图中的零点的存在将辐射减少到用户头部。

32. 发明申请

WO1997021109A1 MOBILE POSITION DETERMINATION 审中-公开
标题翻译：移动位置确定
公开(公告)号：WO1997021109A1
公开(公告)日：1997-06-12
申请号：PCT/GB1996002986
申请日：1996-12-03
申请人： SYMMETRICOM, INC. , FFOULKES-JONES, Geraint
发明人： SYMMETRICOM, INC.
IPC分类号： G01S05/14
CPC分类号： G01S19/07 , G01S19/04 , H04W64/00
摘要： Position determining apparatus comprises a cellular radio system including at least one base station having a base station satellite receiver (6) and position determination means including a cellular mobile station (50) coupled to a local satellite receiver (58), the base station being arranged to transmit base station satellite data including data representing a carrier phase measurement derived from a satellite signal (70) received by the base station satellite receiver (6) to the mobile station (50) via a cellular radio link and the position determination means being arranged to determine its position relative to the base station using local satellite data received by the local satellite receiver (58) and to correct errors in this position determination using base station satellite data. The relative positions of the base stations may be determined automatically with reference to an external positional reference. The external positional reference may be a satellite-based position determining system.
摘要翻译：位置确定装置包括：蜂窝无线电系统，包括具有基站卫星接收机（6）的至少一个基站和包括耦合到本地卫星接收机（58）的蜂窝移动台（50）的位置确定装置，所述基站被布置将基站卫星接收机（6）所接收的表示从卫星信号（70）导出的载波相位测量数据的基站卫星数据通过蜂窝无线电链路发射到移动台（50），并且布置位置确定装置使用本地卫星接收机（58）接收的本地卫星数据来确定其相对于基站的位置，并使用基站卫星数据来校正该位置确定中的错误。基站的相对位置可以参照外部位置参照自动确定。外部位置参考可以是基于卫星的位置确定系统。

33. 发明申请

WO1996041418A1 DIGITAL PHASE DETECTOR EMPLOYING A DIGITALLY CONTROLLABLE DELAY LINE 审中-公开
标题翻译：数字相位检测器采用数字可控延时线
公开(公告)号：WO1996041418A1
公开(公告)日：1996-12-19
申请号：PCT/US1996008937
申请日：1996-06-05
申请人： SYMMETRICOM, INC.
发明人： SYMMETRICOM, INC. , HAMILTON, Michael, M. , MERRISS, Morley, M. , ZAMPETTI, George, P.
IPC分类号： H03L07/081
CPC分类号： H03L7/093 , H03L7/0814
摘要： A digital phase detector composed of: a digitally controllable signal delay device having a signal input, a signal output and a control input, the delay device being operative for conducting a signal from the signal input to the signal output with a time delay having a duration determined by a control signal supplied to the control input, the signal input being connected to receive either an input signal or a digital local clock signal; a phase relation detector connected to receive a first input signal from the signal output of the signal delay device and a second input signal constituted by one of the input signal and the digital local clock signal which is not received by the signal input of the signal delay device, for periodically comparing the phases of the first and second input signals and for producing a binary output signal composed of a succession of signal segments, each segment having a first value when the first input signal is leading the second input signal in phase and a second value when the first input signal is lagging the second input signal in phase; and a digital modulator connected for receiving the binary output signal from the phase relation detector and producing a digital output representative of the magnitude of the phase difference between the input signal and the digital local clock signal based on the values of successive signal segments of the binary output signal produced by the phase relation detector.
摘要翻译：一种数字相位检测器，包括：具有信号输入，信号输出和控制输入的数字可控信号延迟装置，所述延迟装置可操作用于以具有持续时间的时间延迟从信号输入到信号输出传导信号由提供给控制输入的控制信号确定，所述信号输入被连接以接收输入信号或数字本地时钟信号; 相位关系检测器，被连接以从信号延迟装置的信号输出端接收第一输入信号和由输入信号和数字本地时钟信号之一构成的第二输入信号，该信号不由信号延迟的信号输入接收装置，用于周期性地比较第一和第二输入信号的相位，并且用于产生由一系列信号段组成的二进制输出信号，当第一输入信号同相引导第二输入信号时，每个段具有第一值，当第一输入信号相位滞后于第二输入信号时的第二值; 连接的数字调制器，用于从相位关系检测器接收二进制输出信号，并根据二进制信号的连续信号段的值产生代表输入信号和数字本地时钟信号之间的相位差大小的数字输出由相位关系检测器产生的输出信号。

34. 发明公开

EP2039172A4 IMAGE COMPLEXITY COMPUTATION IN PACKET BASED VIDEO BROADCAST SYSTEMS 审中-公开
标题翻译： IMAGE复杂计算的包基于视频广播系统
公开(公告)号：EP2039172A4
公开(公告)日：2011-04-13
申请号：EP06787390
申请日：2006-07-12
申请人： SYMMETRICOM INC
发明人： MOHANDAS PRAVEEN A
IPC分类号： H04N7/173 , H04N17/00
CPC分类号： H04N21/4347 , H04N21/2365 , H04N21/23655 , H04N21/2402

35. 发明公开

EP2025104A2 NETWORK TIME PROTOCOL PRECISION TIMESTAMPING SERVICE 审中-公开
标题翻译：网络时间协议精确时间印花税
公开(公告)号：EP2025104A2
公开(公告)日：2009-02-18
申请号：EP07811895.7
申请日：2007-05-16
申请人： Symmetricom, Inc.
发明人： DOWD, Gregory, Louis
IPC分类号： H04L12/28 , H04J3/06
CPC分类号： H04J3/0673 , H04J3/0697 , H04L69/28
摘要： Embodiments of the present invention set forth a method and system for reducing uncertainty in receive and transmit timestamps created by an NTP server. The uncertainty in the receive timestamps is removed by recording the time-of-arrival in the hardware clock of the NTP server before the incoming packets may be delayed by traversing the various layers of software in a timestamping system. The uncertainty in the transmit timestamps is removed by giving the outgoing packets a timestamp in the future using an estimate of the transmission latency calculated by the latency estimator filter. Subsequently, the actual time-of-departure is used to re-calculate and update the estimate of the transmission latency. In this fashion, superior control of the timestamping function may be implemented in existing NTP servers in a manner that retains interworking compatibility with the current NTP standards.

36. 发明授权

EP0830758B1 DISTRIBUTION OF SYNCHRONIZATION IN A SYNCHRONOUS OPTICAL ENVIRONMENT 失效
标题翻译：同步在同步光环境下配送
公开(公告)号：EP0830758B1
公开(公告)日：2003-05-02
申请号：EP96916851.7
申请日：1996-05-31
申请人： SYMMETRICOM, INC.
发明人： NARASIMHA, Madihally , SHENOI, Kishan
IPC分类号： H04J3/06
CPC分类号： H04J3/0647 , H04J2203/0089
摘要： Apparatus and methods for distributing synchronization throughout a network is disclosed. The distribution of the synchronization is through the use of generating a reference timing signal, and by counting the line clock pulses between the start of a frame and the timing reference signal pulse at a first office and that count is then encoded and transmitted to the next office. At the next office, the transmitted count is decoded and used for regenerating synchronization by counting a number of received line clock pulses from the start of the frame to regenerate the reference timing signal. Particular criteria for selecting the frequencies for the timing reference signal are disclosed.

37. 发明公开

EP0896762A1 MULTIPLE INPUT FREQUENCY LOCKED LOOP 失效
标题翻译：多输入频率控制电路
公开(公告)号：EP0896762A1
公开(公告)日：1999-02-17
申请号：EP97922623.0
申请日：1997-05-02
申请人： SYMMETRICOM, INC.
发明人： ZAMPETTI, George
IPC分类号： G06F13 , G01S19 , G04G7 , H03L7 , H04J3
CPC分类号： G04G7/00 , H03L7/08 , H03L7/087 , H03L7/143 , H04J3/0688
摘要： A dual locked loop is disclosed comparing preferably a GPS signal with an E1 signal and the E1 signal with the output of the loop. The GPS signal is low pass filtered to provide a low pass filtered GPS versus E1 signal that is used as a calibration for a closed loop having a second low pass filter for filtering the comparisons of the E1 and the output signal. By appropriately selecting the filter parameters, the output stability can track the stability of the local oscillator driving the NCO for short term stability, the medium term stability of the E1 signal and the long term stability of the GPS signal.

38. 发明专利

BRPI0707441A2 未知
公开(公告)号：BRPI0707441A2
公开(公告)日：2011-05-03
申请号：BRPI0707441
申请日：2007-02-01
申请人： SYMMETRICOM INC
发明人： ZAMPETTI GEORGE P
IPC分类号： H04J3/06 , G04G5/00 , G06F1/12 , G06F1/14 , G06F15/16 , H04L7/00
摘要： One embodiment of the present invention sets forth a method for autonomously validating the time and frequency data obtained from multiple sources, and generating a suitable estimate of the frequency difference between the client clock and the source. The method includes the steps of protocol data unit validation, offset measurement, minimum offset filtering, and frequency filtering. With these steps, the negative effects of packet delay variation may be mitigated and a frequency estimate is determined for the source in question, together with an associated validity status. Consequently, quality control of the local clock is achieved in packet networks at significantly reduced cost and decreased level of complexity relative to prior art approaches.

39. 发明专利

DE602006006613D1 未知
公开(公告)号：DE602006006613D1
公开(公告)日：2009-06-18
申请号：DE602006006613
申请日：2006-03-31
申请人： SYMMETRICOM INC
发明人： ELLIOT ROBERT MARK
IPC分类号： H04J3/06
摘要： The variable latency associated with standard network forwarding devices is eliminated by forwarding timing packets through a network forwarding device with a constant delay. The network forwarding device of the invention time stamps timing packets that are received by the input ports with a predefined future time, and then outputs the timing packets from the output ports at the predefined time so that the transmission delay through the network forwarding device is the same from any port to any other port.

40. 发明专利

MX2008014768A SERVICIO DE MARCA DE HORA DE PRECISION CON PROTOCOLO DE HORA DE RED. 未知
公开(公告)号：MX2008014768A
公开(公告)日：2009-04-16
申请号：MX2008014768
申请日：2007-05-16
申请人： SYMMETRICOM INC
发明人： DOWD GREGORY LOUIS
IPC分类号： H04L12/28 , H04J3/06
摘要： Modalidades de la presente invención establecen un método y sistema para reducir la incertidumbre en transmitir sellos de hora de recepción y transmisión creados por un servidor de protocolo de tiempo en red (NTP); la incertidumbre en los sellos de hora de recepción se elimina al registrar la hora de llegada en el reloj de soporte físico del servidor NTP antes que se demoren los paquetes entrantes al atravesar los diferentes estratos de software en un sistema de sello de hora; la incertidumbre en los sellos de hora de transmisión se elimina al dar a los paquetes salientes un sello de hora en el futuro usando una estimación de la latencia de transmisión calculada por el filtro calculador de latencia; posteriormente, la hora de salida real se utiliza para recalcular y actualizar el estimado de la latencia de transmisión; de esta forma, se puede implementar un control superior de la función de sello de hora en servidores NTP existentes de manera que mantenga la compatibilidad de interacción con las normas NTP actuales.

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