公开(公告)号：US06661831B1

公开(公告)日：2003-12-09

申请号：US09641305

申请日：2000-08-18

申请人： Ken Umeno

发明人： Ken Umeno

IPC分类号： H04B1707

CPC分类号： H04J13/0022 ,  H04B1/7075 ,  H04J13/10

摘要： A PN sequence output apparatus outputs a PN sequence which is generated by using a Chebyshev polynomial T(a, cos &thgr;)=cos(a &thgr;) for an integer a (2≦a) and which has a length N (1≦N). An accepting section accepts an S (1≦S) number of initial values X1, X2, . . . , Xs each of which is a real number larger than −1 and less than 1, and an S number of degrees p1, p2, . . . , ps each of which is an integral number equal to or larger than 2. A calculation section calculates a Pseudorandom Noise sequence, having a length N, z[1], z[2], . . . , z[N], using the initial values, the degrees, and recurrence formulas xj[1]=Xj, xj[m+1]=T (pj, xj[m]), and z[n]=Πj=1s T(pj, xj[n]), for integers j (1≦j≦S), m (1≦m≦N−1) and n (1≦n≦N). An output section outputs a PN sequence. In this structure, direct spectrum spreading communication is established using the output PN sequence as a spreading code.

摘要翻译： PN序列输出装置输出通过对整数a（2 <= a）使用切比雪夫多项式T（a，cosθ）= cos（θθ）而生成的PN序列，其长度为N（1 < N）。 接受部接受S（1 <= S）个初始值X1，X2。 。 。 ，其中每个都是大于-1且小于1的实数，以及S个度数p1，p2，...。 。 。 ，其中每个都是等于或大于2的整数。计算部分计算具有长度N，z [1]，z [2]的伪随机噪声序列。 。 。 ，z [N]，使用初始值，度数和递推公式xj [1] = Xj，xj [m + 1] = T（pj，xj [m]），z [n] = Pij = 1 对于整数j（1 <= j <= S），m（1 <= m <= N-1）和n（1 <= n <= N），T（pj，xj [n]）。 输出部分输出PN序列。 在该结构中，使用输出PN序列作为扩展码来建立直接频谱扩展通信。

公开(公告)号：US06658048B1

公开(公告)日：2003-12-02

申请号：US09545703

申请日：2000-04-07

申请人： Harri Valio

发明人： Harri Valio

IPC分类号： H04B1707

CPC分类号： G01S19/22 ,  G01S19/30 ,  H04B1/709 ,  H04B2001/70706

摘要： A method for compensating for multipath components in a received CDMA signal comprising a repetitive PRN code uses delay times in addition to the early, late and prompt delay times for determining if a multipath component is present in the received signal, and if so, making an adjustment to the delay time of the replica code generated by a receiver so as to minimize the difference between the correlation values for a delay time equal to −1 chip and a delay time more negative than −1 chip. In this manner, adjustments to the estimation time for the start of the PRN code can be made in a manner which minimizes the effects of multipath components. A system using additional delays and correlators in association with the code phase detector, a code numerical control oscillator and replica code generator is described for performing the above methodology. The methodology is particularly suitable for GPS receivers and may further be used in receivers that receive any type of digital sequence spread spectrum, code division multiple access signals. Compensation for multipath components with 180 degree phase shifts is also made as well as compensation due to smoothing of the triangular correlation function due to RF characteristics and non-ideal PRN codes.

摘要翻译： 用于补偿包括重复PRN码的接收CDMA信号中的多路径分量的方法除了早期，晚期和迅速的延迟时间之外还使用延迟时间来确定接收信号中是否存在多径分量，如果是，则 对由接收机生成的复制码的延迟时间进行调整，以便将等于-1个码片的延迟时间的相关值与延迟时间之间的差最小化到比-1个码片更负的延迟时间。 以这种方式，可以以最小化多路径分量的影响的方式对PRN码的开始的估计时间进行调整。 描述了与代码相位检测器，代码数字控制振荡器和复制代码发生器相关联的使用附加延迟和相关器的系统，用于执行上述方法。 该方法特别适用于GPS接收机，并可进一步用于接收任何类型的数字序列扩频，码分多址信号的接收机。 对于具有180度相移的多路径分量的补偿也是由于由于RF特性和非理想PRN码而导致的三角相关函数的平滑而进行的补偿。

公开(公告)号：US06654408B1

公开(公告)日：2003-11-25

申请号：US09699051

申请日：2000-10-27

申请人： Tamer Adel Kadous ,  Akbar Muhammed Sayeed

发明人： Tamer Adel Kadous ,  Akbar Muhammed Sayeed

IPC分类号： H04B1707

CPC分类号： H04L27/2647 ,  H04B1/712 ,  H04L5/026

摘要： A multi-carrier receiver, which may be utilized for receiving MC-CDMA signals, projects the received signal onto each subcarrier and onto a selected number of adjacent subcarriers. The signals resulting from the projection are combined and decoded to provide a decision statistic signal. The decision statistic signal is evaluated to determine an estimated bit value over each bit length in the transmitted signal. The receiver exploits the effects of imperfections in the communications channel such as fast fading, Doppler and frequency offsets and phase noise, to account for the dispersion of signal energy from a subcarrier to one or more adjacent subcarriers.

摘要翻译： 可以用于接收MC-CDMA信号的多载波接收机将接收到的信号投影到每个子载波上并且到选定数量的相邻子载波上。 由投影产生的信号被组合和解码以提供判定统计信号。 评估判定统计信号以确定发送信号中的每个位长度上的估计位值。 接收机利用通信信道中的缺陷的影响，例如快速衰落，多普勒频率偏移和相位噪声，以解决从副载波到一个或多个相邻子载波的信号能量的分散。

公开(公告)号：US06650687B1

公开(公告)日：2003-11-18

申请号：US09692849

申请日：2000-10-19

申请人： John G. McDonough

发明人： John G. McDonough

IPC分类号： H04B1707

CPC分类号： H04J13/0022 ,  H04B1/707 ,  H04J13/10

摘要： One particular data sequence generator for spread spectrum communications includes a first data access module, a second data access module, and a binary counter for use in repeatedly providing counter values from 0 to 215−1 at a 15-bit output. The first data access module, which may include a read-only memory (ROM), has first and second pseudorandom noise (PN) sequences encoded therein, each having a length of 215. The first data access module has a 15-bit input coupled to the 15-bit output providing the counter values. The first, data access module also has a first bit output to provide a selected PN bit of the first PN sequence and a second bit output to provide a selected PN bit of the second PN sequence responsive to each one of the counter values from 0 to 215−1. The second data access module, which may also include a ROM, has an N-bit input coupled to N lines of the 15-bit output. The second data access module provides Walsh code data of a 2N-by-2N Hadamard matrix responsive to each counter value at the N-bit input.

摘要翻译： 用于扩展频谱通信的一个特定数据序列发生器包括第一数据存取模块，第二数据存取模块和二进制计数器，用于在15位输出端重复地提供从0到2 <15> -1的计数器值。 可以包括只读存储器（ROM）的第一数据访问模块具有在其中编码的第一和第二伪随机噪声（PN）序列，每个具有2 <15>的长度。 第一个数据访问模块具有耦合到15位输出的15位输入，提供计数器值。 第一数据访问模块还具有第一比特输出以提供第一PN序列的所选PN比特和第二比特输出，以响应每个计数器值从0到 2 <15> -1。 也可以包括ROM的第二数据访问模块具有耦合到15位输出的N行的N位输入。 响应于N位输入处的每个计数器值，第二数据访问模块提供2＆lt; N＆gt; - 2＆lt; N＆gt; Hadamard矩阵的沃尔什码数据。

公开(公告)号：US06643317B1

公开(公告)日：2003-11-04

申请号：US09513538

申请日：2000-02-25

申请人： Marc Blumer

发明人： Marc Blumer

IPC分类号： H04B1707

CPC分类号： H04B15/04 ,  H04B2215/064 ,  H04B2215/067

摘要： A digital spread spectrum system provides a simple, digital device and method for reducing electromagnetic interference even where a clock signal to the device is rapidly turned on and off. A primary clock signal drives a signal selector. A signal delay is provided in the circuit to provide delayed clock pulse signals. The signal delay detunes the primary clock signal. By repeatedly switching the delay in and out of the clock signal path, a first signal is generated having a frequency at or about the clock signal, and, a second signal is generated which is displaced slightly from the first signal, but still at or about the clock frequency. By repeatedly switching the delay in and out of the primary clock signal path at a rate greater than the frequency of the clock signal, smaller portions of each primary clock pulse may be parsed for subsequent reaggregation to create a spread spectrum clock signal. As a result, a plurality of spread spectrum clock signals at varying frequencies may be created to spread the energy of the signal over a broader spectrum, thereby lowering the signal energy peak to minimize radiation of electromagnetic emissions at undesirable levels.

摘要翻译： 数字扩频系统提供了一种简单的数字设备和方法，即使在快速打开和关闭设备的时钟信号的情况下，也可减少电磁干扰。 主时钟信号驱动信号选择器。 在电路中提供信号延迟以提供延迟的时钟脉冲信号。 信号延迟会消除主时钟信号。 通过重复地切换时钟信号路径的延迟，产生具有或在其周围的时钟信号的频率的第一信号，并且产生从第一信号稍微偏移但仍然在或在其周围的第二信号 时钟频率。 通过以大于时钟信号的频率的速率反复切换主时钟信号路径的延迟，可以分析每个主时钟脉冲的较小部分用于随后的再聚合以产生扩频时钟信号。 结果，可以创建变化频率的多个扩频时钟信号以在更宽的频谱上扩展信号的能量，从而降低信号能量峰值，以使不期望的电平下的电磁辐射的辐射最小化。

公开(公告)号：US06608858B1

公开(公告)日：2003-08-19

申请号：US09491349

申请日：2000-01-26

申请人： Gilbert C. Sih ,  Avneesh Agrawal ,  Mark Roh ,  Brian K. Butler ,  Raghu Challa

发明人： Gilbert C. Sih ,  Avneesh Agrawal ,  Mark Roh ,  Brian K. Butler ,  Raghu Challa

IPC分类号： H04B1707

CPC分类号： H04B1/7087 ,  H04B1/7115 ,  H04B1/7117 ,  H04B2201/70701 ,  H04L27/0014 ,  H04L2027/0032 ,  H04L2027/0057 ,  H04L2027/0087

摘要： A method and apparatus for frequency tracking is described. The present invention provides a tracking mechanism for removing the effects of error due to frequency offset as well as compensation for frequency error due to doppler in a plurality of multipath signals. Each finger of a RAKE receiver utilizing the present invention will compute a frequency error for that finger. The weighted average of all of these frequency errors is calculated and filtered to provide a control signal for varying the frequency of IF and RF frequency synthesizers, accounting for the common frequency offset seen at each finger. Additionally, each finger is equipped with a rotator for providing frequency adjustment specific to that finger. The frequency of each finger is adjusted through feedback of the frequency error for that finger.

摘要翻译： 描述了用于频率跟踪的方法和装置。 本发明提供了一种用于消除由于频率偏移引起的误差的影响的跟踪机制以及由多个多径信号中的多普勒引起的频率误差的补偿。 利用本发明的RAKE接收机的每个手指将计算该手指的频率误差。 计算并滤波所有这些频率误差的加权平均值，以提供用于改变IF和RF频率合成器的频率的控制信号，从而考虑每个手指处的共同频率偏移。 此外，每个手指配备有用于提供特定于该手指的频率调节的旋转器。 每个手指的频率通过该手指的频率误差的反馈进行调整。

公开(公告)号：US06606347B1

公开(公告)日：2003-08-12

申请号：US09556406

申请日：2000-04-24

申请人： Tatsuya Ishii

发明人： Tatsuya Ishii

IPC分类号： H04B1707

CPC分类号： H04B1/71075

摘要： Each of path search unit 41 . . . 4N performs a path-searching on a received signal rin to output a primary path timing signal 8 indicating primary path timings. Each of IEUs 11 . . . 1N in a first stage performs a despreading or the like on the basis of the primary path timing signal 8 to generate a symbol replica signal 51 and a chip replica signal 6. Subtractor 31 subtracts the sum of chip replica signals 6 from the received signal rin to generate a residual signal 7. Each of path search units 41 . . . 4N performs a path-searching on the residual signal 7, and outputs a secondary path signal 9 indicating secondary path timings. A primary path timing of which SIR is low and which has a temporary secondary path timing which is near to the primary path timing is not selected as a secondary path timing but the corresponding temporary secondary path is selected as the secondary path timing. A primary path timing of which SIR is not low or which does not have a temporary secondary path timing which is near to the primary path timing is selected as a secondary path timing. Each of IEUs 11 . . . 1N in the second and the following stages performs a despreading or the like on the basis of the secondary path timing signal 9.

摘要翻译： 路径搜索单元41中的每一个。 。 。 4N对接收到的信号rin执行路径搜索以输出指示主路径定时的主路径定时信号8。 每个IEU 11。 。 。 第一级中的1N在主路径定时信号8的基础上进行解扩等，生成符号复制信号51和芯片复制信号6.减法器31从接收信号rin中减去片复制信号6的和 以产生残留信号7.每个路径搜索单元41。 。 。 4N对残差信号7进行路径搜索，并且输出指示次路径定时的次路径信号9。 没有选择SIR为低并且具有接近主路径定时的临时次路径定时的主路径定时作为次路径定时，而是选择对应的临时辅助路径作为次路径定时。 选择SIR不低或不具有接近主路径定时的临时次路径定时的主路径定时作为次路径定时。 每个IEU 11。 。 。 在第二和第二级中的1N根据次路径定时信号9进行解扩等。

公开(公告)号：US06563812B1

公开(公告)日：2003-05-13

申请号：US09416279

申请日：1999-10-12

申请人： Parthapratim De

发明人： Parthapratim De

IPC分类号： H04B1707

CPC分类号： H04B1/71052

摘要： A receiver in a code-division-multiple-access network includes a forward detector, a first feedback detector, a set of second feedback detectors, a slicer and an arithmetic logic unit for detecting each one of the multiple transmitted signals. The forward detector has an input connected to receive the sum of the multiple transmitted signals. The arithmetic logic has an input connected to an output of the forward detector. The slicer has an input connected to an output of the arithmetic logic unit. The first feedback detector has an input connected to an output of the slicer and an output is connected to the input of the arithmetic logic unit. Each of the second feedback detectors has an input connected to the output of a slicer for each of the other slicers and an output is connected to the input of the arithmetic logic unit. The output of the slicer provides the detected signal, for each transmitter.

摘要翻译： 码分多址网络中的接收机包括前向检测器，第一反馈检测器，一组第二反馈检测器，限幅器和用于检测多个发射信号中的每一个的算术逻辑单元。 正向检测器具有连接的输入端以接收多个发射信号的和。 算术逻辑具有连接到正向检测器的输出的输入。 切片器具有连接到算术逻辑单元的输出的输入。 第一反馈检测器具有连接到限幅器的输出的输入端，并且输出端连接到算术逻辑单元的输入端。 每个第二反馈检测器具有连接到用于每个其他限幅器的限幅器的输出的输入，并且输出连接到算术逻辑单元的输入。 切片器的输出为每个发射器提供检测到的信号。

公开(公告)号：US06526090B1

公开(公告)日：2003-02-25

申请号：US09474035

申请日：1999-12-28

申请人： Aris Papasakellariou

发明人： Aris Papasakellariou

IPC分类号： H04B1707

CPC分类号： H04B1/711 ,  H04B2201/70707

摘要： A method (32) of operating a spread spectrum communications receiver (20). The method demodulates a current path group with a demodulator (28), wherein the current path group comprises one or more current paths and wherein the demodulating step comprises demodulating the one or more current paths with a respective one more demodulation elements. The method also determines (42) one or more survey groups at the receiver, wherein each survey group comprises of a unique combination of one or more new paths and zero or more current paths. Still further, the method determines a quality measure (52) of the current path group and (53) of one or more survey groups. Further, the method selectively assigns (62) a selected one of the survey groups to respective elements of the demodulator in place of the current path group in response to a comparison of the quality measure of the selected one of the survey groups with the quality measure of the current path group. Finally, the quality measure is responsive to a power of each path in a group and multiple forms of diversity within a group.

摘要翻译： 一种操作扩展频谱通信接收机（20）的方法（32）。 该方法利用解调器（28）对当前路径组进行解调，其中当前路径组包括一个或多个电流路径，并且其中解调步骤包括用相应的一个以上解调元件解调一个或多个电流路径。 该方法还确定（42）在接收器处的一个或多个测量组，其中每个测量组包括一个或多个新路径和零个或更多个当前路径的唯一组合。 此外，该方法确定当前路径组的质量度量（52）和一个或多个测量组的（53）。 此外，响应于所选择的一个调查组的质量测量与质量测量的比较，该方法选择性地（62）将所选择的一个测量组分配给解调器的各个元件来代替当前路径组 的当前路径组。 最后，质量度量是响应于一组中的每个路径的功率和组内的多种形式的多样性。

公开(公告)号：US06512784B2

公开(公告)日：2003-01-28

申请号：US09795181

申请日：2001-03-01

申请人： Donald L. Schilling

发明人： Donald L. Schilling

IPC分类号： H04B1707

CPC分类号： H04W52/343 ,  H04B1/707 ,  H04W48/14 ,  H04W52/16 ,  H04W88/10

摘要： An improvement to a spread-spectrum, code-division-multiple-access (CDMA) cellular system having multiple circuit-switched (CS) remote stations, multiple packet-switched (PS) remote stations and a base station per cell. The CS-remote station transmits a spread-spectrum CDMA signal, with a chip rate of fc, with a CS-symbol rate of fb, and with a power level PCS. The PS-remote station transmits a spread-spectrum CDMA signal with the chip rate of fc, PS-symbol rate fp, and with a power level PPS. The power level PPS from the PS-remote station and the power level PCS from the CS-remote station are related by a relation of the CS-symbol rate and the PS-symbol rate to efficiently share system capacity.