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公开(公告)号：US08428198B2
公开(公告)日：2013-04-23
申请号：US11376986
申请日：2006-03-15
IPC分类号： H04L27/06
CPC分类号： H04L27/2657 , H04L27/2607 , H04L27/2665 , H04L27/2678 , H04L27/2695
摘要： A frequency tracking method and apparatus is provided. A receiver receives OFDM symbols and determines associated frequency offset. A frequency error estimator selects a cross correlation window for determining frequency offset based on timing offset. A symbol timing estimator is used to determine the timing offset.
摘要翻译： 提供了一种频率跟踪方法和装置。 接收机接收OFDM符号并确定相关的频率偏移。 频率误差估计器基于定时偏移来选择用于确定频率偏移的互相关窗口。 使用符号定时估计器来确定定时偏移。
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公开(公告)号：US08102949B2
公开(公告)日：2012-01-24
申请号：US12646543
申请日：2009-12-23
申请人： Fuyun Ling , Seong Taek Chung , Jinxia Bai , Thomas Sun
发明人： Fuyun Ling , Seong Taek Chung , Jinxia Bai , Thomas Sun
IPC分类号： H03D3/22
CPC分类号： H04L27/3488 , H04L1/0045 , H04L1/0065 , H04L1/0066 , H04L27/2604 , H04L2001/0098
摘要： A system and method are provided for generating bit log likelihood ratio (LLR) values for two-layered Quadrature Phase-Shift Keying (QPSK) turbo decoding in a wireless communications user terminal (UT). The method includes receiving a two-layered QPSK signal with an energy ratio that is unknown, but typically defined as either k12 or k22. The method selects a mismatched energy ratio (k2) between k12 and k22, and generating bit LLR values for two-layered QPSK turbo decoding, using the mismatched k2 energy ratio. For example, if the received two-layered QPSK signal is known to have an energy ratio of about 4 or about 6.25. Then, k2 is selected to be about 5.0625. Alternately stated, the mismatched k2 energy ratio in selected by determining the approximate midpoint between k12 and k22.
摘要翻译： 提供了一种用于在无线通信用户终端（UT）中生成用于双层正交相移键控（QPSK）turbo解码的比特对数似然比（LLR）值的系统和方法。 该方法包括以未知的能量比接收两层QPSK信号，但通常定义为k12或k22。 该方法选择k12和k22之间的不匹配能量比（k2），并使用不匹配的k2能量比生成双层QPSK turbo解码的比特LLR值。 例如，如果已知所接收的两层QPSK信号具有约4或约6.25的能量比。 然后，选择k2为约5.0625。 或者说，通过确定k12和k22之间的近似中点，选择的不匹配的k2能量比。
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公开(公告)号：US20100098192A1
公开(公告)日：2010-04-22
申请号：US12646543
申请日：2009-12-23
申请人： Fuyun Ling , Seong Taek Chung , Jinxia Bai , Thomas Sun
发明人： Fuyun Ling , Seong Taek Chung , Jinxia Bai , Thomas Sun
CPC分类号： H04L27/3488 , H04L1/0045 , H04L1/0065 , H04L1/0066 , H04L27/2604 , H04L2001/0098
摘要： A system and method are provided for generating bit log likelihood ratio (LLR) values for two-layered Quadrature Phase-Shift Keying (QPSK) turbo decoding in a wireless communications user terminal (UT). The method includes receiving a two-layered QPSK signal with an energy ratio that is unknown, but typically defined as either k12 or k22. The method selects a mismatched energy ratio (k2) between k12 and k22, and generating bit LLR values for two-layered QPSK turbo decoding, using the mismatched k2 energy ratio. For example, if the received two-layered QPSK signal is known to have an energy ratio of about 4 or about 6.25. Then, k2 is selected to be about 5.0625. Alternately stated, the mismatched k2 energy ratio in selected by determining the approximate midpoint between k12 and k22.
摘要翻译： 提供了一种用于在无线通信用户终端（UT）中生成用于双层正交相移键控（QPSK）turbo解码的比特对数似然比（LLR）值的系统和方法。 该方法包括以未知的能量比接收两层QPSK信号，但通常定义为k12或k22。 该方法选择k12和k22之间的不匹配能量比（k2），并使用不匹配的k2能量比生成双层QPSK turbo解码的比特LLR值。 例如，如果已知所接收的两层QPSK信号具有约4或约6.25的能量比。 然后，选择k2为约5.0625。 或者说，通过确定k12和k22之间的近似中点，选择的不匹配的k2能量比。
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公开(公告)号：US20090316835A1
公开(公告)日：2009-12-24
申请号：US12467303
申请日：2009-05-17
CPC分类号： H04L27/3488 , H04W52/0245 , Y02D70/00
摘要： A wireless communication apparatus in a hierarchically coded modulation system can use error control mechanisms generated during decoding of base layer information to predict a probability of successful demodulation of enhancement layer information. Performance in the demodulation of the base layer correlates to performance in the demodulation of the enhancement layer. The receiver can determine whether to attempt demodulation of temporally correlated enhancement layer data based in part on the predicted probability of success. If the receiver determines not to demodulate the enhancement layer, the receiver can power down the enhancement layer demodulator, or otherwise minimize the power expended in the enhancement layer demodulator.
摘要翻译： 分级编码调制系统中的无线通信装置可以使用在解码基层信息期间产生的误差控制机制来预测增强层信息的成功解调的概率。 基层解调性能与增强层解调性能有关。 接收机可以部分地基于预测的成功概率来确定是否尝试对时间相关的增强层数据的解调。 如果接收机确定不解调增强层，则接收机可以将增强层解调器断电，或以其他方式最小化增强层解调器中消耗的功率。
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公开(公告)号：US20100220816A1
公开(公告)日：2010-09-02
申请号：US12777540
申请日：2010-05-11
IPC分类号： H04L27/00
CPC分类号： H04L27/3488 , H04W52/0245 , Y02D70/00
摘要： A wireless communication apparatus in a hierarchically coded modulation system can use error control mechanisms generated during decoding of base layer information to predict a probability of successful demodulation of enhancement layer information. Performance in the demodulation of the base layer correlates to performance in the demodulation of the enhancement layer. The receiver can determine whether to attempt demodulation of temporally correlated enhancement layer data based in part on the predicted probability of success. If the receiver determines not to demodulate the enhancement layer, the receiver can power down the enhancement layer demodulator, or otherwise minimize the power expended in the enhancement layer demodulator.
摘要翻译： 分级编码调制系统中的无线通信装置可以使用在解码基层信息期间产生的误差控制机制来预测增强层信息的成功解调的概率。 基层解调性能与增强层解调性能有关。 接收机可以部分地基于预测的成功概率来确定是否尝试对时间相关的增强层数据的解调。 如果接收机确定不解调增强层，则接收机可以将增强层解调器断电，或以其他方式最小化增强层解调器中消耗的功率。
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公开(公告)号：US08401503B2
公开(公告)日：2013-03-19
申请号：US11358996
申请日：2006-02-21
申请人： Seong Taek Chung , Vinay Murthy , Alok Kumar Gupta , Fuyun Ling
发明人： Seong Taek Chung , Vinay Murthy , Alok Kumar Gupta , Fuyun Ling
IPC分类号： H04B1/18
CPC分类号： H03J7/04 , H03J1/0083
摘要： Techniques for performing frequency control using dual-loop automatic frequency control (AFC) are described. The dual-loop AFC includes an inner loop that corrects short-term frequency variations (e.g., due to Doppler effect) and an outer loop that corrects long-term frequency variations (e.g., due to component tolerances and temperature variations). In one design, a first inner loop is implemented for frequency control of a first system (e.g., a broadcast system), a second inner loop is implemented for frequency control of a second system (e.g., a cellular system), and at least one outer loop is implemented for adjusting a reference frequency used to receive signals from the first and second systems. Each inner loop estimates and corrects the frequency error in an input signal for the associated system and may be enabled when receiving the input signal from the system. The reference frequency may be used for frequency downconversion, sampling and/or other purposes.
摘要翻译： 描述了使用双回路自动频率控制（AFC）进行频率控制的技术。 双回路AFC包括校正短期频率变化（例如，由于多普勒效应引起的）的内部循环和校正长期频率变化（例如由于部件公差和温度变化）的外部回路。 在一种设计中，为第一系统（例如，广播系统）的频率控制实现第一内环，为第二系统（例如，蜂窝系统）的频率控制实现第二内环，并且至少一个 实现外部环路，用于调整用于从第一和第二系统接收信号的参考频率。 每个内循环估计和校正相关系统的输入信号中的频率误差，并且当从系统接收输入信号时可以使能频率误差。 参考频率可用于下变频，采样和/或其他目的。
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公开(公告)号：US07660368B2
公开(公告)日：2010-02-09
申请号：US11330652
申请日：2006-01-11
申请人： Fuyun Ling , Seong Taek Chung , Jinxia Bai , Thomas Sun
发明人： Fuyun Ling , Seong Taek Chung , Jinxia Bai , Thomas Sun
IPC分类号： H03D3/22
CPC分类号： H04L27/3488 , H04L1/0045 , H04L1/0065 , H04L1/0066 , H04L27/2604 , H04L2001/0098
摘要： A system and method are provided for generating bit log likelihood ratio (LLR) values for two-layered Quadrature Phase-Shift Keying (QPSK) turbo decoding in a wireless communications user terminal (UT). The method includes receiving a two-layered QPSK signal with an energy ratio that is unknown, but typically defined as either k12 or k22. The method selects a mismatched energy ratio (k2) between k12 and k22, and generating bit LLR values for two-layered QPSK turbo decoding, using the mismatched k2 energy ratio. For example, if the received two-layered QPSK signal is known to have an energy ratio of about 4 or about 6.25. Then, k2 is selected to be about 5.0625. Alternately stated, the mismatched k2 energy ratio in selected by determining the approximate midpoint between k12 and k22.
摘要翻译： 提供了一种用于在无线通信用户终端（UT）中生成用于双层正交相移键控（QPSK）turbo解码的比特对数似然比（LLR）值的系统和方法。 该方法包括以未知的能量比接收两层QPSK信号，但通常定义为k12或k22。 该方法选择k12和k22之间的不匹配能量比（k2），并使用不匹配的k2能量比生成双层QPSK turbo解码的比特LLR值。 例如，如果已知所接收的两层QPSK信号具有约4或约6.25的能量比。 然后，选择k2为约5.0625。 或者说，通过确定k12和k22之间的近似中点，选择的不匹配的k2能量比。
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公开(公告)号：US08874998B2
公开(公告)日：2014-10-28
申请号：US12467303
申请日：2009-05-17
CPC分类号： H04L27/3488 , H04W52/0245 , Y02D70/00
摘要： A wireless communication apparatus in a hierarchically coded modulation system can use error control mechanisms generated during decoding of base layer information to predict a probability of successful demodulation of enhancement layer information. Performance in the demodulation of the base layer correlates to performance in the demodulation of the enhancement layer. The receiver can determine whether to attempt demodulation of temporally correlated enhancement layer data based in part on the predicted probability of success. If the receiver determines not to demodulate the enhancement layer, the receiver can power down the enhancement layer demodulator, or otherwise minimize the power expended in the enhancement layer demodulator.
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9.发明授权Automatic frequency control for a wireless communication system with multiple subcarriers 有权具有多个子载波的无线通信系统的自动频率控制公开(公告)号：US08009775B2
公开(公告)日：2011-08-30
申请号：US11372931
申请日：2006-03-09
申请人： Vinay Murthy , Alok Kumar Gupta , Seong Taek Chung , Fuyun Ling
发明人： Vinay Murthy , Alok Kumar Gupta , Seong Taek Chung , Fuyun Ling
CPC分类号： G06F1/0353 , H04L5/0007 , H04L5/0048 , H04L27/2659 , H04L27/266 , H04L27/2662 , H04L27/2675 , H04L27/2678
摘要： Techniques for performing frequency control in an OFDM system are described. In one aspect, frequency acquisition is performed based on a received pilot, and frequency tracking is performed based on received OFDM symbols. For frequency acquisition, an initial frequency error estimate may be derived based on the received pilot, and an automatic frequency control (AFC) loop may be initialized with the initial frequency error estimate. For frequency tracking, a frequency error estimate may be derived for each received OFDM symbol, and the AFC loop may be updated with the frequency error estimate. Frequency error in input samples is corrected by the AFC loop with the initial frequency error estimate as well as the frequency error estimate for each received OFDM symbol. In another aspect, a variable number of samples of a received OFDM symbol are selected, e.g., based on the received OFDM symbol timing, for use for frequency error estimation.
摘要翻译： 描述在OFDM系统中执行频率控制的技术。 在一个方面，基于接收到的导频执行频率采集，并且基于接收的OFDM符号执行频率跟踪。 对于频率获取，可以基于接收到的导频来导出初始频率误差估计，并且可以利用初始频率误差估计来初始化自动频率控制（AFC）循环。 对于频率跟踪，可以针对每个接收的OFDM符号导出频率误差估计，并且可以用频率误差估计来更新AFC循环。 通过具有初始频率误差估计的AFC回路以及每个接收的OFDM符号的频率误差估计来校正输入采样中的频率误差。 在另一方面，例如基于所接收的OFDM符号定时，选择接收的OFDM符号的可变数目的样本，以用于频率误差估计。
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10.发明申请Automatic frequency control for a wireless communication system with multiple subcarriers 有权具有多个子载波的无线通信系统的自动频率控制公开(公告)号：US20060215778A1
公开(公告)日：2006-09-28
申请号：US11372931
申请日：2006-03-09
申请人： Vinay Murthy , Alok Gupta , Seong Taek Chung , Fuyun Ling
发明人： Vinay Murthy , Alok Gupta , Seong Taek Chung , Fuyun Ling
IPC分类号： H04K1/10
CPC分类号： G06F1/0353 , H04L5/0007 , H04L5/0048 , H04L27/2659 , H04L27/266 , H04L27/2662 , H04L27/2675 , H04L27/2678
摘要： Techniques for performing frequency control in an OFDM system are described. In one aspect, frequency acquisition is performed based on a received pilot, and frequency tracking is performed based on received OFDM symbols. For frequency acquisition, an initial frequency error estimate may be derived based on the received pilot, and an automatic frequency control (AFC) loop may be initialized with the initial frequency error estimate. For frequency tracking, a frequency error estimate may be derived for each received OFDM symbol, and the AFC loop may be updated with the frequency error estimate. Frequency error in input samples is corrected by the AFC loop with the initial frequency error estimate as well as the frequency error estimate for each received OFDM symbol. In another aspect, a variable number of samples of a received OFDM symbol are selected, e.g., based on the received OFDM symbol timing, for use for frequency error estimation.
摘要翻译： 描述在OFDM系统中执行频率控制的技术。 在一个方面，基于接收到的导频执行频率采集，并且基于接收的OFDM符号执行频率跟踪。 对于频率获取，可以基于接收到的导频来导出初始频率误差估计，并且可以利用初始频率误差估计来初始化自动频率控制（AFC）循环。 对于频率跟踪，可以针对每个接收的OFDM符号导出频率误差估计，并且可以用频率误差估计来更新AFC循环。 通过具有初始频率误差估计的AFC回路以及每个接收的OFDM符号的频率误差估计来校正输入采样中的频率误差。 在另一方面，例如基于所接收的OFDM符号定时，选择接收到的OFDM符号的可变数目的样本，以用于频率误差估计。
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