公开(公告)号：US06246717B1

公开(公告)日：2001-06-12

申请号：US09185418

申请日：1998-11-03

申请人： Xiaofen Chen ,  Linley F. Gumm ,  Dana E. Whitlow ,  Larry R. Lockwood

发明人： Xiaofen Chen ,  Linley F. Gumm ,  Dana E. Whitlow ,  Larry R. Lockwood

IPC分类号： H04Q120

CPC分类号： H04B3/46 ,  H04L1/205

摘要： A system and method for in-service transmitter phase noise measurements determines phase nonlinearity by way of comparing unfiltered signal samples and regenerated reference signal samples to calculate phase nonlinearity error. Linear distortion is removed from the received signal samples in order to truly characterize nonlinear behavior of the transmitter. The unfiltered signal samples are generated without applying the receiver shaping filtering. Reference signal samples are regenerated from estimated transmitted symbols derived from the unfiltered signal samples. The transmitted symbols are estimated using a segmented slicer which dynamically estimates constellation decision levels from the unfiltered signal samples. A weighted, least-square based polynomial regression is performed on phase error samples of the unfiltered signal samples to estimate a phase nonlinear error function while suppressing the impact of other non-systematic distortions. The nonlinear phase error is removed from the phase error to produce phase noise containing carrier phase jitter and additive noise. A threshold is determined for replacing phase error values outside the threshold with random values having a distribution equivalent to the carrier phase jitter. The carrier phase jitter may be displayed as a power spectrum of the phase noise.

摘要翻译： 用于在线发射机相位噪声测量的系统和方法通过比较未滤波的信号样本和再生参考信号样本来确定相位非线性，以计算相位非线性误差。 从接收的信号采样中去除线性失真，以便真实地表征发射机的非线性特性。 在不应用接收机整形滤波的情况下生成未滤波的信号样本。 参考信号样本从未滤波的信号样本导出的估计的传输符号中再生。 使用分段限幅器来估计所发送的符号，其从未滤波的信号样本中动态地估计星座决定级别。 对未滤波信号样本的相位误差样本进行加权最小二乘回归，以估计相位非线性误差函数，同时抑制其他非系统失真的影响。 从相位误差去除非线性相位误差，产生包含载波相位抖动和加性噪声的相位噪声。 确定阈值以用具有等于载波相位抖动的分布的随机值来替换阈值之外的相位误差值。 载波相位抖动可以显示为相位噪声的功率谱。

公开(公告)号：US06275523B1

公开(公告)日：2001-08-14

申请号：US09185417

申请日：1998-11-03

申请人： Xiaofen Chen ,  Linley F. Gumm ,  Thomas L. Kuntz

发明人： Xiaofen Chen ,  Linley F. Gumm ,  Thomas L. Kuntz

IPC分类号： H04B1700

CPC分类号： H04L1/206 ,  H04B17/18

摘要： A system for in-service nonlinearity measurements measures such nonlinearities by way of comparing received linear error-corrected unfiltered signal samples with re-generated reference signal samples to calculate magnitude and phase nonlinear error values. Linear distortion is removed from the received signal samples in order to truly characterize nonlinear behavior of the transmitter. The linear error-corrected received signal samples are generated without applying the receiver shaping filtering. Reference signal samples are re-generated from estimated transmitted symbols from the unfiltered linear error-corrected received signal samples. The transmitted symbols are estimated using a multi-region slicer which dynamically estimates constellation decision levels from the unfiltered signal samples. A weighted, least-square based polynomial regression is performed on magnitude and phase nonlinear error values to estimate magnitude and phase nonlinear error functions while suppressing the impact of other non-systematic distortions.

摘要翻译： 用于在线非线性测量的系统通过将接收到的线性误差校正的未滤波信号样本与重新产生的参考信号样本进行比较来测量这种非线性，以计算幅度和相位非线性误差值。 从接收的信号采样中去除线性失真，以便真实地表征发射机的非线性特性。 在不应用接收机整形滤波的情况下生成线性误差校正的接收信号样本。 从未滤波的线性误差校正接收信号样本的估计的发射符号重新产生参考信号样本。 使用多区域限幅器来估计所发送的符号，该多区域限幅器从未滤波的信号样本中动态地估计星座决定级别。 对幅度和相位非线性误差值进行加权最小二乘法多项式回归，以估计幅度和相位非线性误差函数，同时抑制其他非系统失真的影响。

公开(公告)号：US06701265B2

公开(公告)日：2004-03-02

申请号：US10093171

申请日：2002-03-05

申请人： Thomas C. Hill ,  Xiaofen Chen ,  Soraya J. Matos ,  Leroy J. Willmann ,  Kyle L. Bernard ,  Linley F. Gumm

发明人： Thomas C. Hill ,  Xiaofen Chen ,  Soraya J. Matos ,  Leroy J. Willmann ,  Kyle L. Bernard ,  Linley F. Gumm

IPC分类号： G01D1800

CPC分类号： G01R27/32 ,  G01R35/005

摘要： An improved calibration method for a vector network analyzer stores sparse calibration data, interpolates system error data from the sparse calibration data for each measurement by the vector network analyzer, and creates calibrated measurement data from the system error data and uncorrected measurement data at each measurement frequency. The sparse calibration data may be generated by measuring every Nth frequency step over a calibration frequency range greater than a specified measurement frequency range, or by measuring every frequency step over the calibration frequency range and compressing the resulting measurement data. The interpolation may be achieved by using a curve-fit algorithm, such as a parametric polynomial curve fitting algorithm.

摘要翻译： 用于矢量网络分析仪的改进的校准方法存储稀疏校准数据，通过矢量网络分析仪从每个测量的稀疏校准数据内插系统误差数据，并从系统误差数据和每个测量频率的未校正测量数据创建校准的测量数据 。 可以通过在大于指定测量频率范围的校准频率范围上测量每​​第N个频率步长，或者通过测量校准频率范围上的每个频率步长并压缩所得到的测量数据来生成稀疏校准数据。 可以通过使用诸如参数多项式曲线拟合算法的曲线拟合算法来实现内插。

公开(公告)号：US06384589B1

公开(公告)日：2002-05-07

申请号：US09826495

申请日：2001-04-04

申请人： Linley F. Gumm ,  Thomas L. Kuntz ,  Xiaofen Chen

发明人： Linley F. Gumm ,  Thomas L. Kuntz ,  Xiaofen Chen

IPC分类号： G01R1320

CPC分类号： H04L27/0002

摘要： Reference frequency spur cancellation in a synthesized measurement receiver is achieved by determining for any given frequency to which the receiver is tuned a list of integer multipliers of the reference frequency that produce spurious signals in the receiver's passband. For those values the amplitude and phase for each spurious signal is determined in the digital domain and subtracted from the digital signal from the receiver. The reference frequency is then offset slightly and the measurement repeated. The maximum values between each measurement are combined to produce a measurement for the input signal without spurious signals.

摘要翻译： 合成测量接收机中的参考频率杂散消除通过确定接收机调谐的任何给定频率来确定在接收机的通带中产生杂散信号的参考频率的整数乘法器的列表。 对于这些值，每个杂散信号的幅度和相位在数字域中确定，并从接收机的数字信号中减去。 参考频率稍微偏移，重复测量。 每个测量之间的最大值被组合以产生没有杂散信号的输入信号的测量。

公开(公告)号：US06542112B1

公开(公告)日：2003-04-01

申请号：US10093152

申请日：2002-03-06

申请人： Xiaofen Chen ,  Soraya J. Matos

发明人： Xiaofen Chen ,  Soraya J. Matos

IPC分类号： G01S740

CPC分类号： H04B1/123 ,  G01R27/32 ,  G01R29/10

摘要： A method of interference cancellation in antenna test measurements is achieved by acquiring an acquisition at a test port of an antenna test instrument in response to an internal signal source, stamping the data acquisition time, and measuring a signal vector that has both a reflection signal component and an interference signal component. Another acquisition at the test port without the internal signal source is obtained with limited data points to detect whether there are interference signals. If there is significant interference power, a complete acquisition is obtained without the internal signal source, the data acquisition time is stamped, and an interference vector that has only the interference signal is measured. Then the interference frequency is measured, an interference phase shift between the two data acquisitions is calculated, an interference vector for the combined reflection/interference vector is predicted using the interference vector and the phase shift, and the predicted interference vector is subtracted from the signal vector to obtain the actual reflection signal for the antenna in the absence of interference.

摘要翻译： 天线测试测量中的干扰消除方法是通过在天线测试仪器的测试端口响应于内部信号源获取采集，标记数据采集时间，并测量具有反射信号分量的信号矢量 和干扰信号分量。 在没有内部信号源的测试端口处的另一个采集是通过有限的数据点获得的，以检测是否存在干扰信号。 如果存在明显的干扰功率，则无需内部信号源就可以获得完整的采集，数据采集时间被标记，并且仅测量干扰信号的干扰矢量。 然后测量干扰频率，计算两次数据采集之间的干扰相移，使用干扰矢量和相移预测组合反射/干扰矢量的干涉矢量，并从信号中减去预测干扰矢量 向量以在没有干扰的情况下获得天线的实际反射信号。

公开(公告)号：US07184406B2

公开(公告)日：2007-02-27

申请号：US09967555

申请日：2001-09-28

申请人： Kathryn A. Engholm ,  Xiaofen Chen

发明人： Kathryn A. Engholm ,  Xiaofen Chen

IPC分类号： H04J1/16

CPC分类号： H04B1/707 ,  H04B2201/70703

摘要： A display of code domain power (CDP) for a code domain multiple access (CDMA) signal having multiple spreading factors is in the form of a three-dimensional graphic having as axes code domain power, code index and spreading factor to provide a visual indication of both power and spreading factor for active codes. Sub-codes of base codes may be identified by any suitable means, such as highlighting. Sub-codes may be suppressed and the power level of the base codes adjusted accordingly to represent the total power of the active codes.

摘要翻译： 用于具有多个扩展因子的码域多址（CDMA）信号的码域功率（CDP）的显示是具有作为轴码域功率，码索引和扩展因子的三维图形的形式，以提供视觉指示 有效代码的功率和扩频因子。 可以通过任何合适的方式来识别基本代码的子代码，例如突出显示。 可以抑制子代码，并且相应地调整基本代码的功率电平以表示活动代码的总功率。

公开(公告)号：US06366621B1

公开(公告)日：2002-04-02

申请号：US09185218

申请日：1998-11-03

申请人： Thomas L. Kuntz ,  Xiaofen Chen

发明人： Thomas L. Kuntz ,  Xiaofen Chen

IPC分类号： H03D124

CPC分类号： H04L27/066 ,  H04L2027/0026 ,  H04L2027/0067

摘要： A method of estimating pilot signal phase embedded in a wideband digital signal modulating a RF signal that is down converted to an intermediate frequency and digitized includes the steps of summing a block of the signal samples for removing the modulation data and generating data values representative of vector locations of the pilot signal with each data value representing an angular rotation of the pilot signal vector, and calculating the phase of the pilot signal by determining the arc tangent of the data values. The method produces a computationally efficient narrow band filter generated at the pilot signal frequency by simple addition of the digital data values. The method is usable in a software based 8-VSB digital television demodulation system.

摘要翻译： 一种估计嵌入在频域数字信号中的导频信号相位的方法，该宽带数字信号调制被转换成中频并被数字化的RF信号包括以下步骤：对用于去除调制数据的信号采样块进行求和并产生代表矢量的数据值 导频信号的位置，每个数据值表示导频信号矢量的角度旋转，并且通过确定数据值的反正切来计算导频信号的相位。 该方法通过简单地添加数字数据值来产生在导频信号频率下产生的计算有效的窄带滤波器。 该方法可用于基于软件的8-VSB数字电视解调系统。

公开(公告)号：US06741642B1

公开(公告)日：2004-05-25

申请号：US09055049

申请日：1998-04-03

申请人： Kyle L. Bernard ,  Xiaofen Chen ,  Thomas L. Kuntz

发明人： Kyle L. Bernard ,  Xiaofen Chen ,  Thomas L. Kuntz

IPC分类号： G06F1100

CPC分类号： H04N21/2383 ,  H04L1/24 ,  H04L27/04 ,  H04N17/00 ,  H04N21/4382

摘要： A modulation analyzer includes a smoothing processor which processes the coordinates of symbol landing points to generate a curve that optimally fits the landing points under a selected criterion.

摘要翻译： 调制分析器包括平滑处理器，其处理符号着陆点的坐标以产生在选定标准下最佳地适合着陆点的曲线。

公开(公告)号：US06636722B1

公开(公告)日：2003-10-21

申请号：US09660561

申请日：2000-09-12

申请人： Donald J. Dalebroux ,  Xiaofen Chen

发明人： Donald J. Dalebroux ,  Xiaofen Chen

IPC分类号： H04B1700

CPC分类号： H04B17/20

摘要： A method of broadband receiver amplitude/phase normalization uses internal normalization sources—a thermally compensated noise source and a pseudo random sequence generator. A calibrated signal is applied to the input of the broadband receiver and processed by a digital signal processor to generate a gain versus frequency table. Then the internal noise source is applied to the input of the broadband receiver and process by a digital signal processor to generate a noise level versus frequency table. Finally the internal pseudo random sequence generator applies a pseudo random sequence waveform to the input of the broadband receiver, the pseudo random sequence waveform being process by the digital signal processor to generate equalization filter coefficients for the IF stages.

摘要翻译： 宽带接收机振幅/相位归一化的方法使用内部归一化源 - 热补偿噪声源和伪随机序列发生器。 经校准的信号被施加到宽带接收机的输入端并被数字信号处理器处理以产生增益对频率表。 然后将内部噪声源施加到宽带接收机的输入端并由数字信号处理器进行处理以产生噪声电平对频率表。 最后，内部伪随机序列发生器将伪随机序列波形应用于宽带接收机的输入，伪随机序列波形由数字信号处理器处理以产生用于IF级的均衡滤波器系数。

公开(公告)号：US06366629B1

公开(公告)日：2002-04-02

申请号：US09185421

申请日：1998-11-03

申请人： Xiaofen Chen ,  Thomas L. Kuntz

发明人： Xiaofen Chen ,  Thomas L. Kuntz

IPC分类号： H04L700

CPC分类号： H04L7/0029 ,  H04L7/042 ,  H04L7/06 ,  H04N17/004

摘要： A method of estimating symbol timing phase and rate offsets of a sampled digitally modulated signal having repetitive symbol sync sequences includes the steps of estimating symbol sync sequence locations in a block of signal samples using a cross-correlation with a reference pattern of ideal symbol sync sequences. Signal samples within subranges defining the symbol sync sequences in the block of signal samples are filtered for removing intersymbol interference. An iterative process of cross-correlation of the filtered signal samples within the subranges using the reference pattern of ideal symbol sync sequences and an ideal symbol sync correction pattern generates timing phase and rate offset values that are used to derive filter coefficients for resampling the filtered signal samples within the subranges using an interpolating filter. The rate offset value is derived using a linear model and performing an optimal estimation. The iterative cross-correlation and resampling process continues until the rate of change of timing phase and rate offset values are minimized. The timing phase and rate offset values are provided to a resampling FIR filter for generating properly synchronized signal samples that are time aligned to symbol-spaced boundaries.

摘要翻译： 估计具有重复符号同步序列的采样数字调制信号的符号定时相位和速率偏移的方法包括以下步骤：使用与理想符号同步序列的参考图案的互相关来估计信号样本块中的符号同步序列位置 。 在信号样本块中定义符号同步序列的子范围内的信号样本被滤波以去除符号间干扰。 使用理想符号同步序列和理想符号同步校正模式的参考图案，子范围内的滤波后的信号样本的互相关的迭代过程产生用于导出滤波器系数以重新采样滤波信号的定时相位和速率偏移值 使用内插滤波器在子范围内的样本。 使用线性模型导出速率偏移值并执行最优估计。 迭代互相关和重采样过程一直持续到定时相位和速率偏移值的变化率最小化。 定时相位和速率偏移值被提供给重采样FIR滤波器，用于产生与符号间隔边界时间对准的适当同步的信号采样。