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    GPS receiver having a fast time to first fix
    73.
    发明授权
    GPS receiver having a fast time to first fix 失效
    GPS接收机具有快速首次固定的时间

    公开(公告)号：US5798732A

    公开(公告)日：1998-08-25

    申请号：US716112

    申请日：1996-09-19

    申请人： Ralph F. Eshenbach

    发明人： Ralph F. Eshenbach

    IPC分类号： G01S1/00 ,  G01S5/00 ,  H04L27/30 ,  H04B7/185

    CPC分类号： G01S19/235 ,  G01S19/243 ,  G01S5/0018

    摘要： A global positioning system (GPS) receiver and a method having a fast time to first fix (TTFF) using GPS signal Doppler frequency shifts for correcting the local clock time and using information for an expected GPS message for synchronizing the corrected local clock time to GPS time. The GPS receiver includes radio frequency (RF) circuitry for receiving and downconverting a spread spectrum GPS satellite signal, a correlator for despreading the downconverted GPS signal and providing a GPS bit stream, a clock for providing a local time, and a processor including an executable code. The executable code includes a Doppler correction code for improving the accuracy of the local time by comparing a measured and a calculated Doppler frequency shift for the GPS satellite signal from three or more GPS satellites, and a GPS synchronization code for synchronizing the local time so that the timing of a replica bit stream based upon information for an expected GPS message matches the timing a GPS bit stream received in the GPS satellite signal.

    摘要翻译： 一种全球定位系统（GPS）接收机和一种使用GPS信号多普勒频移进行首次固定的快速时间（TTFF）的方法，用于校正本地时钟时间，并使用用于将校正后的本地时钟时间与GPS同步的预期GPS信息 时间。 GPS接收机包括用于接收和下变频扩频GPS卫星信号的射频（RF）电路，用于解扩下变频GPS信号并提供GPS位流的相关器，用于提供本地时间的时钟，以及包括可执行程序的处理器 码。 可执行代码包括用于通过比较来自三个或更多个GPS卫星的GPS卫星信号的测量和计算的多普勒频移以及用于同步本地时间的GPS同步码来改善本地时间的精度的多普勒校正码， 基于预期GPS消息的信息的复制比特流的定时与在GPS卫星信号中接收的GPS比特流的定时相匹配。

    Data reproducing apparatus for spread spectrum signal
    75.
    发明授权
    Data reproducing apparatus for spread spectrum signal 失效
    用于扩频信号的数据再现装置

    公开(公告)号：US5778023A

    公开(公告)日：1998-07-07

    申请号：US597255

    申请日：1996-02-06

    申请人： Nobuhiko Ideta ,  Ryuzo Nishi

    发明人： Nobuhiko Ideta ,  Ryuzo Nishi

    IPC分类号： H04J13/00 ,  H04B1/7073 ,  H04B7/26 ,  H04W56/00 ,  H04B15/00 ,  H04K1/00 ,  H04L27/30

    CPC分类号： H04B1/707

    摘要： The present invention aims to present a data reproducing apparatus for a spread spectrum signal which can synchronize quickly and accurately, using a low cost phase lock loop circuit, in spread spectrum communication. To achieve the object, a peak timing is detected from the output of a correlation circuit for despreading, the output of a correlation circuit exceeding a designated level during a bit rate period near which center the peak timing is put is integrated and data is reproduced according to the polarity of the integrated output signal. Thus, the influence of multi-path fading is reduced, synchronization is not needed in a spread band and TDD synchronization can be held quickly.

    摘要翻译： 本发明的目的在于提供一种扩展频谱信号的数据再现装置，其能够在扩展频谱通信中使用低成本锁相环电路快速而准确地同步。 为了实现该目的，从用于解扩的相关电路的输出检测到峰值定时，在峰值定时的中心附近的比特率周期期间超过指定电平的相关电路的输出被整合，并且根据 到集成输出信号的极性。 因此，减少了多径衰落的影响，扩频中不需要同步，并且可以快速地保持TDD同步。

    Adaptive spread spectrum receiver
    76.
    发明授权
    Adaptive spread spectrum receiver 失效
    自适应扩频接收机

    公开(公告)号：US5757845A

    公开(公告)日：1998-05-26

    申请号：US446717

    申请日：1995-05-30

    申请人： Kazuhiko Fukawa ,  Hiroshi Suzuki

    发明人： Kazuhiko Fukawa ,  Hiroshi Suzuki

    IPC分类号： H04B1/707 ,  H04B1/709 ,  H04B7/10 ,  H04J13/00 ,  H04B15/00 ,  H04K1/00 ,  H04L27/30

    CPC分类号： H04B1/7093 ,  H04B1/7115

    摘要： Sampled signals SPS of a spread-spectrum received signal are fed to matched filters 12.sub.1, to 12.sub.4, wherein they are despread. A spreading code of a desired signal is used as a despreading code in the matched filter 12.sub.1, and a plurality of spreading codes which are orthogonal to the spreading code of the desired signal and orthogonal to one another are used for despreading in the matched filters 12.sub.2 to 12.sub.4. Outputs x.sub.1 to x.sub.4 from the filters 12.sub.1 to 12.sub.4 are multipled by weighting coefficients w.sub.1 to w.sub.4 ; the multiplied outputs are linearly combined into a combined signal DCS. A coefficient control part 37 is supplied with the signals x.sub.1 to X.sub.4 to be multiplied by the weighting coefficients w.sub.1 to w.sub.4 and the combined signal DCS and determines the weighting coefficients w.sub.1 to w.sub.4 by an algorithm that minimizes the average power of the combined signal DCS under a constraint on the weighting coefficients w.sub.1 to w.sub.4.

    摘要翻译： PCT No.PCT / JP95 / 00179 Sec。 371日期：1995年5月30日 102（e）日期1995年5月30日PCT提交1995年2月9日PCT公布。 出版物WO95 / 22214 PCT 日期1995年7月17日扩频接收信号的采样信号SPS被馈送到匹配滤波器121至124，其中它们被解扩。 期望信号的扩展码用作匹配滤波器121中的解扩展码，并且在匹配滤波器122中用于解扩，并且与所需信号的扩展码正交并且彼此正交的多个扩展码用于解扩 从滤波器121至124的输出x1至x4乘以加权系数w1至w4; 相乘的输出被线性组合成组合信号DCS。 向系数控制部分37提供要乘以加权系数w1至w4的信号x1至x4以及组合信号DCS，并且通过使组合信号DCS的平均功率最小化的算法来确定加权系数w1至w4 对加权系数w1至w4的约束。

    System employing continuous-time dissipative pseudorandom dynamics for communications and measurement
    77.
    发明授权
    System employing continuous-time dissipative pseudorandom dynamics for communications and measurement 失效
    采用连续时间耗散伪随机动力学进行通信和测量的系统

    公开(公告)号：US5737360A

    公开(公告)日：1998-04-07

    申请号：US492285

    申请日：1995-06-19

    申请人： Geoffrey Grinstein ,  Neil Gershenfeld

    发明人： Geoffrey Grinstein ,  Neil Gershenfeld

    IPC分类号： H04B1/707 ,  H04B15/00 ,  H04K1/00 ,  H04L27/30

    CPC分类号： H04B1/707

    摘要： A communication and/or measurement system includes in a a transmitter an analog feedback system that modulates a pseudo-random noise signal with a message signal to produce a wideband signal for transmission. A receiver, which demodulates the wideband signal to recover the message signal, includes an associated analog feedback system that reproduces the noise signal based on the received signal. The analog feedback systems (AFS) are continuous-time generalizations of a linear feedback shift register ("LFSR"). The AFS are characterized by a function that agrees with the function that characterizes the LFSR, at the points at which that function is defined. Further, the AFS characterizing function has stable periodic orbits at these values, and the stable periodic orbits are attractors. The AFS thus produces a signal that relaxes on to a nearest periodic orbit that generalizes to continuous time the maximal sequence produced by the corresponding LFSR. The AFS in the transmitter, which operates in accordance with a harmonic oscillator, is characterized by the following differential equation: ##EQU1## where the .alpha..sub.i 's are the coefficients of the maximum length polynomial used to produce the maximal sequence. The AFS in the receiver is characterized by the following differential equation: ##EQU2##

    摘要翻译： 通信和/或测量系统在发射机中包括模拟反馈系统，其利用消息信号来调制伪随机噪声信号以产生用于传输的宽带信号。 解调宽带信号以恢复消息信号的接收机包括相关联的模拟反馈系统，其基于接收到的信号再现噪声信号。 模拟反馈系统（AFS）是线性反馈移位寄存器（“LFSR”）的连续时间泛化。 AFS的特征在于与定义该功能的点相一致的功能与表征LFSR的功能一致。 此外，AFS特征函数在这些值处具有稳定的周期轨道，并且稳定的周期轨道是吸引子。 因此，AFS产生松弛到最近的周期性轨道的信号，其将相应LFSR产生的最大序列广义化为连续时间。 发射机中根据谐波振荡器工作的AFS的特征在于以下微分方程：其中αi是用于产生最大序列的最大长度多项式的系数。 接收机中的AFS的特征在于以下微分方程： + TR

    Technique to permit rapid acquisition and alert channel signalling for base station-to-user link of an orthogonal CDMA (OCDMA) communication system
    78.
    发明授权
    Technique to permit rapid acquisition and alert channel signalling for base station-to-user link of an orthogonal CDMA (OCDMA) communication system 失效
    允许对正交CDMA（OCDMA）通信系统的基站到用户链路的快速采集和警告信道信令的技术

    公开(公告)号：US5717713A

    公开(公告)日：1998-02-10

    申请号：US343974

    申请日：1994-11-18

    申请人： Francis Natali

    发明人： Francis Natali

    IPC分类号： H04B1/7075 ,  H04B1/7085 ,  H04B1/7087 ,  H04J11/00 ,  H04J13/00 ,  H04B15/00 ,  H04K1/00 ,  H04L27/30

    CPC分类号： H04B1/7075 ,  H04B1/7085 ,  H04B1/7087 ,  H04J13/0003

    摘要： An OCDMA spread spectrum communication system is provided with a PN encoded acquisition channel signal which is free of Radamacher functions. This provides a technique for very rapid acquisition of the PN code and data symbol timing; enables accurate PN chip time tracking with a minimum of power; enables accurate frequency tracking with a minimum of power; provides a technique for accurate signal power measurement at the receiver; enables the receiver to maintain code lock during deep fades; and penetrates into areas of high attenuation for paging or to alert user that he has a call waiting.

    摘要翻译： OCDMA扩频通信系统具有没有Radamacher功能的PN编码采集信道信号。 这提供了用于非常快速地获取PN码和数据符号定时的技术; 以最小的功率实现精确的PN芯片时间跟踪; 能够以最小功率进行精确的频率跟踪; 提供了一种在接收机处进行精确信号功率测量的技术; 使接收机能够在深度衰减期间维持代码锁定; 并渗透到高衰减区域进行寻呼或提醒用户他有一个呼叫等待。

    Apparatus and method for signal identification
    79.
    发明授权
    Apparatus and method for signal identification 失效
    用于信号识别的装置和方法

    公开(公告)号：US5696789A

    公开(公告)日：1997-12-09

    申请号：US399274

    申请日：1995-03-06

    申请人： Robert V. Jones ,  Richard J. Saggio ,  John W. Zscheile, Jr.

    发明人： Robert V. Jones ,  Richard J. Saggio ,  John W. Zscheile, Jr.

    IPC分类号： H04B1/707 ,  H04B15/00 ,  H04K1/00 ,  H04L27/30

    CPC分类号： H04B1/707

    摘要： A novel code division multiple access (CDMA) system and apparatus is provided which permits a plurality of encoded modulated data messages to be transmitted simultaneously on the same channel in one frequency band as a composite CDMA signal. An identification signal is generated and spread by a spreading signal having a duty cycle less than fifty percent to produce a combined signal which is transmitted to a receiver having a tapped delay with a plurality of taps each of which produce a replica of the received combined signal delayed by an odd multiple of the duty cycle of the spreading signal. Each of the replica signals is multiplied by a predetermined weighted value to produce weighted delayed signals and a controller responsive to the received combined signal, is employed for controlling individual weighted delayed signals which are then combined to suppress the spreading signal leaving the identification signal.

    摘要翻译： 提供了一种新颖的码分多址（CDMA）系统和装置，其允许在作为复合CDMA信号的一个频带中的同一信道上同时发送多个编码调制数据消息。 通过占空比小于百分之五十的扩展信号产生并扩展识别信号，以产生组合信号，该组合信号被发送到具有抽头延迟的接收机，多个抽头每个抽头产生接收到的组合信号的副本 延迟了扩展信号占空比的奇数倍。 将每个复制信号乘以预定的加权值以产生加权的延迟信号，并且响应于接收到的组合信号的控制器被用于控制然后被组合的各个加权延迟信号，以抑制离开识别信号的扩展信号。

    Spread spectrum communications system
    80.
    再颁专利
    Spread spectrum communications system 失效
    扩频通信系统

    公开(公告)号：USRE35650E

    公开(公告)日：1997-11-04

    申请号：US490955

    申请日：1995-06-15

    申请人： Andrzej Partyka ,  Lee F. Crowley

    发明人： Andrzej Partyka ,  Lee F. Crowley

    IPC分类号： H04B1/707 ,  H04L27/30

    CPC分类号： H04B1/707

    摘要： A spread spectrum communication system for direct sequence transmission of digital information having a modulation format which is particularly suitable for indoor communication within residential, office and industrial structures. The modulation format combines BPSK or MSK spreading with FM carrier modulation by data bits and a carrier frequency shift whose magnitude is related to both a chip rate and a spreading sequence length. The carrier, chip clock and data clock are all synchronous and the sequence length is an integral submultiple of the bit length. The system reduces the frequency error between the transmitter chip clock and the receiver chip clock to permit the elimination of a code phase tracking loop in the receiver to reduce the receiver complexity. The receiver has an extended dynamic range which makes possible the reception of very strong signal without an automatic gain control loop (AGC) as well as reducing the time needed for code phase acquisition. The transmission system is highly resistant to CW jamming and short distance multipath effects.

    摘要翻译： 一种用于直接序列传输数字信息的扩频通信系统，其具有特别适用于住宅，办公和工业结构内的室内通信的调制格式。 调制格式将BPSK或MSK扩展与FM载波调制结合数据位和载波频移，其幅度与码片速率和扩频序列长度相关。 载波，芯片时钟和数据时钟均为同步，序列长度为位长度的整数倍。 该系统减少了发射机芯片时钟和接收器芯片时钟之间的频率误差，以便消除接收机中的码相位跟踪环路，以减少接收机的复杂度。 接收机具有扩展的动态范围，这使得可以在没有自动增益控制回路（AGC）的情况下接收非常强的信号，并且减少代码相位采集所需的时间。 传输系统对CW干扰和短距离多径效应具有很高的抗干扰能力。