专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明授权

US06678339B1 Globally optimum maximum likelihood estimation of joint carrier frequency offset and symbol timing error in multi-carrier systems 失效
标题翻译：多载波系统中联合载波频率偏移和符号定时误差的全局最优最大似然估计
公开(公告)号：US06678339B1
公开(公告)日：2004-01-13
申请号：US09496890
申请日：2000-02-02
申请人： Navid Lashkarian
发明人： Navid Lashkarian
IPC分类号： H03D100
CPC分类号： H04L27/2657 , H04L27/2662 , H04L27/2668 , H04L27/2689
摘要： A method for synchronizing multi-carrier signals in an orthogonal frequency division modulation (OFDM) data transmission system is disclosed which provides maximum likelihood estimation of timing offset and frequency offset. The estimates are able to compensate the estimation error over an entire span of observed data samples. The method requires no training sequence thus enabling blind frequency compensation. The method provides a joint probability density function for the estimates which consists of two terms; one generated from observed data received during a first interval and one generated from observed data received during a second, following, interval. The estimates provided by the method are therefore maximal likelihood over the entire span of observed signals and are a significant improvement over estimates provided by methods based only observations during the first interval. The method is mathematically robust and computationally and statistically efficient. Comparison studies generated by computer simulation graphically display the improved estimates provided by the invention over previous estimation techniques.
摘要翻译：公开了一种在正交频分调制（OFDM）数据传输系统中同步多载波信号的方法，其提供定时偏移和频率偏移的最大似然估计。估计可以补偿观测数据样本整个跨度的估计误差。该方法不需要训练序列，从而实现盲频补偿。该方法为由两个项组成的估计提供联合概率密度函数; 从在第一间隔期间接收的观测数据生成的一个，以及在第二间隔期间接收到的观测数据产生的一个。因此，该方法提供的估计是在观察信号的整个跨度上的最大可能性，并且比仅基于第一间隔期间的观察的方法提供的估计值显着改善。该方法在数学上是稳健的，计算上和统计学上有效的。通过计算机模拟产生的比较研究以图形方式显示了本发明提供的改进的估计与先前的估计技术。

2. 发明授权

US08665931B2 Calibration of communication processing path 失效
标题翻译：通信处理路径的校准
公开(公告)号：US08665931B2
公开(公告)日：2014-03-04
申请号：US13539175
申请日：2012-06-29
申请人： Ali Afsahi , Utku Seckin , Colin Fraser , Navid Lashkarian , Konrad Kratochwil , Arya Reza Behzad , Dengwei Fu
发明人： Ali Afsahi , Utku Seckin , Colin Fraser , Navid Lashkarian , Konrad Kratochwil , Arya Reza Behzad , Dengwei Fu
IPC分类号： H04L5/16
CPC分类号： H03F1/0222 , H03F1/0266 , H03F1/223 , H03F2200/18
摘要： Communication processing paths include distortions, such as DC offset in the baseband analog path, local oscillator feed-through distortion, and nonlinearity of gm's and power amplifiers which are calibrated for, separately or in combination. The cascaded DC offset and nonlinear distortions are modeled separately or in combination using even-and-odd order polynomials. A loopback path from the output of one or more distortion causing devices passes through a measurement and calculation module. The calculation module calculates predistortion polynomial's coefficients which will be stored in a look-up table to be used by a baseband predistorter to calibrate the path. The look-up table is stored locally or remotely.
摘要翻译：通信处理路径包括失真，例如基带模拟路径中的DC偏移，本地振荡器馈通失真以及gm和功率放大器的非线性，其被单独地或组合地校准。级联DC偏移和非线性失真是单独建模的，或者使用偶数和奇数阶多项式组合。来自一个或多个引起失真的设备的输出的回送路径通过测量和计算模块。计算模块计算将被存储在由基带预失真器使用以校准路径的查找表中的预失真多项式系数。查找表存储在本地或远程。

3. 发明授权

US07027543B1 Minimum variance unbiased and moment estimators of carrier frequency offset in multi-carrier systems 失效
标题翻译：多载波系统中载波频率偏移的最小方差无偏估计和力矩估计
公开(公告)号：US07027543B1
公开(公告)日：2006-04-11
申请号：US09556858
申请日：2000-04-21
申请人： Navid Lashkarian
发明人： Navid Lashkarian
IPC分类号： H04L7/00
CPC分类号： H04L27/2657 , H04L27/2662 , H04L27/2676
摘要： A class of non data-aided cyclic based robust estimators for frequency offset estimation of multi-carrier systems is disclosed. The use of sufficient statistics provides a minimum variance unbiased (MVU) estimate of the frequency offset under complete knowledge of timing offset error. The Neyman-Fisher factorization theorem and Rao-Blackwell-Lehmann-Scheffe theorem are used to identify the sufficient statistic and appropriate mapping functions. It is shown that there is but one function of the sufficient statistics which results in the minimum variance estimate among the possible class of cyclic-based estimators. Also, a moment estimator of frequency offset is provided to obtain a consistent estimate of carrier offset under uncertain symbol timing error. The moment estimator does not rely on any probabilistic assumptions. Thus, its performance is insensitive to the distribution of the additive noise. A unified structure characterizing both the MVU and moment estimators, as well as a maximum likelihood estimator of a related, copending application is disclosed.
摘要翻译：公开了一种用于多载波系统的频偏估计的非数据辅助循环的鲁棒估计器。在完全了解定时偏移误差的情况下，使用足够的统计数据提供频偏的最小方差无偏估计（MVU）。 Neyman-Fisher因子分解定理和Rao-Blackwell-Lehmann-Scheffe定理用于识别足够的统计量和适当的映射函数。可以看出，只有一个功能足够的统计量导致了可能的基于循环的估计量之间的最小方差估计。此外，提供频率偏移的力矩估计器以在不确定符号定时误差下获得载波偏移的一致估计。时刻估计器不依赖于任何概率假设。因此，其性能对加性噪声的分布不敏感。公开了表征MVU和力矩估计器的统一结构，以及相关的共同未决申请的最大似然估计器。

4. 发明授权

US07203252B2 Minimum variance unbiased and moment estimators of carrier frequency offset in multi-carrier systems 有权
标题翻译：多载波系统中载波频率偏移的最小方差无偏估计和力矩估计
公开(公告)号：US07203252B2
公开(公告)日：2007-04-10
申请号：US11195219
申请日：2005-08-02
申请人： Navid Lashkarian
发明人： Navid Lashkarian
IPC分类号： H04L27/00 , H04L27/06 , H04L27/28
CPC分类号： H04L27/2657 , H04L27/2662 , H04L27/2676
摘要： A class of non data-aided cyclic based robust estimators for frequency offset estimation of multi-carrier systems is disclosed. The use of sufficient statistics provides a minimum variance unbiased (MVU) estimate of the frequency offset under complete knowledge of timing offset error. The Neyman-Fisher factorization theorem and Rao-Blackwell-Lehmann-Scheffe theorem are used to identify the sufficient statistic and appropriate mapping functions. It is shown that there is but one function of the sufficient statistics which results in the minimum variance estimate among the possible class of cyclic-based estimators. Also, a moment estimator of frequency offset is provided to obtain a consistent estimate of carrier offset under uncertain symbol timing error. The moment estimator does not rely on any probabilistic assumptions. Thus, its performance is insensitive to the distribution of the additive noise. A unified structure characterizing both the MVU and moment estimators, as well as a maximum likelihood estimator of a related, copending application is disclosed.
摘要翻译：公开了一种用于多载波系统的频偏估计的非数据辅助循环的鲁棒估计器。在完全了解定时偏移误差的情况下，使用足够的统计数据提供频偏的最小方差无偏估计（MVU）。 Neyman-Fisher因子分解定理和Rao-Blackwell-Lehmann-Scheffe定理用于识别足够的统计量和适当的映射函数。可以看出，只有一个功能足够的统计量导致了可能的基于循环的估计量之间的最小方差估计。此外，提供频率偏移的力矩估计器以在不确定符号定时误差下获得载波偏移的一致估计。时刻估计器不依赖于任何概率假设。因此，其性能对加性噪声的分布不敏感。公开了表征MVU和力矩估计器的统一结构，以及相关的共同未决申请的最大似然估计器。

5. 发明申请

US20050271175A1 Minimum variance unbiased and moment estimators of carrier frequency offset in multi-carrier systems 有权
标题翻译：多载波系统中载波频率偏移的最小方差无偏估计和力矩估计
公开(公告)号：US20050271175A1
公开(公告)日：2005-12-08
申请号：US11195219
申请日：2005-08-02
申请人： Navid Lashkarian
发明人： Navid Lashkarian
IPC分类号： H04L7/00 , H04L27/06 , H04L27/26
CPC分类号： H04L27/2657 , H04L27/2662 , H04L27/2676
摘要： A class of non data-aided cyclic based robust estimators for frequency offset estimation of multi-carrier systems is disclosed. The use of sufficient statistics provides a minimum variance unbiased (MVU) estimate of the frequency offset under complete knowledge of timing offset error. The Neyman-Fisher factorization theorem and Rao-Blackwell-Lehmann-Scheffe theorem are used to identify the sufficient statistic and appropriate mapping functions. It is shown that there is but one function of the sufficient statistics which results in the minimum variance estimate among the possible class of cyclic-based estimators. Also, a moment estimator of frequency offset is provided to obtain a consistent estimate of carrier offset under uncertain symbol timing error. The moment estimator does not rely on any probabilistic assumptions. Thus, its performance is insensitive to the distribution of the additive noise. A unified structure characterizing both the MVU and moment estimators, as well as a maximum likelihood estimator of a related, copending application is disclosed.
摘要翻译：公开了一种用于多载波系统的频偏估计的非数据辅助循环的鲁棒估计器。在完全了解定时偏移误差的情况下，使用足够的统计数据提供频偏的最小方差无偏估计（MVU）。 Neyman-Fisher因子分解定理和Rao-Blackwell-Lehmann-Scheffe定理用于识别足够的统计量和适当的映射函数。可以看出，只有一个功能足够的统计量导致了可能的基于循环的估计量之间的最小方差估计。此外，提供频率偏移的力矩估计器以在不确定符号定时误差下获得载波偏移的一致估计。时刻估计器不依赖于任何概率假设。因此，其性能对加性噪声的分布不敏感。公开了表征MVU和力矩估计器的统一结构，以及相关的共同未决申请的最大似然估计器。

6. 发明申请

US20130287076A1 CALIBRATION OF COMMUNICATION PROCESSING PATH 失效
标题翻译：通信处理路径校准
公开(公告)号：US20130287076A1
公开(公告)日：2013-10-31
申请号：US13539175
申请日：2012-06-29
申请人： Ali Afsahi , Utku Seckin , Colin Fraser , Navid Lashkarian , Konrad Kratochwil , Arya Reza Behzad , Dengwei Fu
发明人： Ali Afsahi , Utku Seckin , Colin Fraser , Navid Lashkarian , Konrad Kratochwil , Arya Reza Behzad , Dengwei Fu
IPC分类号： H04B15/00 , H04L25/49
CPC分类号： H03F1/0222 , H03F1/0266 , H03F1/223 , H03F2200/18
摘要： Communication processing paths include distortions, such as DC offset in the baseband analog path, local oscillator feed-through distortion, and nonlinearity of gm's and power amplifiers which are calibrated for, separately or in combination. The cascaded DC offset and nonlinear distortions are modeled separately or in combination using even-and-odd order polynomials. A loopback path from the output of one or more distortion causing devices passes through a measurement and calculation module. The calculation module calculates predistortion polynomial's coefficients which will be stored in a look-up table to be used by a baseband predistorter to calibrate the path. The look-up table is stored locally or remotely.
摘要翻译：通信处理路径包括失真，例如基带模拟路径中的DC偏移，本地振荡器馈通失真以及gm和功率放大器的非线性，其被单独地或组合地校准。级联DC偏移和非线性失真是单独建模的，或者使用偶数和奇数阶多项式组合。来自一个或多个引起失真的设备的输出的回送路径通过测量和计算模块。计算模块计算将被存储在由基带预失真器使用以校准路径的查找表中的预失真多项式系数。查找表存储在本地或远程。

7. 发明授权

US07006800B1 Signal-to-noise ratio (SNR) estimator in wireless fading channels 有权
标题翻译：无线衰落信道中的信噪比（SNR）估计器
公开(公告)号：US07006800B1
公开(公告)日：2006-02-28
申请号：US10457057
申请日：2003-06-05
申请人： Navid Lashkarian , Karim Nassiri-Toussi
发明人： Navid Lashkarian , Karim Nassiri-Toussi
IPC分类号： H04B17/00
CPC分类号： H04B17/336 , H04B17/26 , H04B17/382
摘要： A signal-to-noise estimator is provided for estimating the signal-to-noise ratio in wireless fading channels. The estimator can be applied to likelihood ratio estimation of turbo decoders in third generation wide-band code division multiple access (WCDMA) systems. Time-multiplexed samples of pilot symbols from a wireless receiver are supplied to the estimator to obtain individual estimates of signal power and/or noise power. The estimator uses a de-correlating filter in which the coefficients are known functions (such as eigen-vectors) of the auto-correlation matrix for a wireless channel. The decorrelating filter is used by the estimator to map an observation vector into a set of statistically independent samples. The energy of each vector component is computed individually and combined to produce an aggregate sum for the vector. The aggregate sum can be subtracted from the pilot tone power in order to produce an estimate of noise power.
摘要翻译：提供了用于估计无线衰落信道中的信噪比的信噪比估计器。估计器可以应用于第三代宽带码分多址（WCDMA）系统中turbo解码器的似然比估计。来自无线接收机的导频符号的时分多路复用样本被提供给估计器以获得信号功率和/或噪声功率的单独估计。估计器使用去相关滤波器，其中系数是用于无线信道的自相关矩阵的已知函数（诸如特征向量）。估计器使用去相关滤波器将观测矢量映射成一组统计独立的样本。每个矢量分量的能量被单独计算并组合以产生矢量的总和。可以从导频音功率中减去总和，以产生噪声功率的估计。

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式