公开(公告)号：US08611471B2

公开(公告)日：2013-12-17

申请号：US13435945

申请日：2012-03-30

申请人： Saurabh Mishra ,  Parag Naik ,  Subrahmanya Kondageri Shankaraiah ,  S Harish Krishnan ,  Gururaj Padaki

发明人： Saurabh Mishra ,  Parag Naik ,  Subrahmanya Kondageri Shankaraiah ,  S Harish Krishnan ,  Gururaj Padaki

IPC分类号： H04L27/00

CPC分类号： H04L27/0014 ,  H04L2027/003 ,  H04L2027/0065

摘要： A system and method for reducing implementation complexity for estimation of a Carrier Frequency Offset (CFO) and a Symbol Timing Offset (STO) for an input signal for spectrally shaped multiple communication standards. The system is implemented by replacing multiplier with shifters. The system includes a CFO estimation block, a STO estimation block, and a band extraction block that extracts a lower band edge and an upper band edge of the input signal. The STO estimation block includes (i) a sample error generation block that computes a sampling timing error value, and (ii) a Phase Lock Loop block that estimates a frequency error and a phase error corresponding to the sampling timing error value. The CFO estimation block includes (i) a carrier offset error generation block that generates a carrier offset error value, and (ii) a leaky average block for performing a filter operation.

摘要翻译： 用于降低用于频谱形状的多通信标准的输入信号的载波频偏（CFO）和符号定时偏移（STO）的实现复杂度的系统和方法。 该系统通过用移位器替换乘法器来实现。 该系统包括CFO估计块，STO估计块和提取输入信号的较低频带边沿和上边带边缘的频带提取块。 STO估计块包括（i）计算采样定时误差值的采样误差产生块，以及（ii）估计与采样定时误差值对应的频率误差和相位误差的锁相环块。 CFO估计块包括（i）产生载波偏移误差值的载波偏移误差产生块，和（ii）用于执行滤波操作的泄漏平均块。

公开(公告)号：US07869551B2

公开(公告)日：2011-01-11

申请号：US11874337

申请日：2007-10-18

申请人： S Harish Krishnan ,  Parag Naik

发明人： S Harish Krishnan ,  Parag Naik

IPC分类号： H04L7/00

CPC分类号： H04L27/2662 ,  H04L27/2607 ,  H04L27/2665

摘要： At a receiver incoming coded OFDM Symbol Data are passed through a Coarse Symbol Timing Synchronization module to determine the approximate start of the symbol. In one embodiment this is accomplished through correlation. The symbol is then passed through an FFT (2K or 8K, depending on the mode desired by the receiver). Since the Coarse Symbol Timing Synchronization module only determines an approximate start point of the symbol, a process of fine synchronization is used to adjust this approximate start point and determine a more accurate start point of the symbol. In this manner, the receiver is enabled to process COFDM symbols in DVB-T transmissions (where the symbols include a cyclic prefix to overcome echoes). One output of an FFT operation is magnitude. Magnitude is used for Channel Estimation (or Channel Correction). Another output of an FFT operation is phase discontinuity or rotations. Phase discontinuities are used in a fine synchronization process to determine the number of phase discontinuities. Phase discontinuity data of the symbol is passed through an N-Point FFT.

摘要翻译： 在接收机输入的OFDM符号数据被传送通过粗符号定时同步模块来确定符号的大致开始。 在一个实施例中，这是通过相关来实现的。 然后，该符号通过FFT（2K或8K，取决于接收机所需的模式）。 由于粗符号定时同步模块仅确定符号的近似开始点，因此使用精细同步的过程来调整该近似起始点并确定符号的更准确的起始点。 以这种方式，接收机能够处理DVB-T传输中的COFDM符号（其中符号包括循环前缀以克服回声）。 FFT运算的一个输出是幅度。 幅度用于信道估计（或信道校正）。 FFT运算的另一个输出是相位不连续或旋转。 相位不连续性用于精细同步过程以确定相位不连续性的数量。 符号的相位不连续数据通过N点FFT。

公开(公告)号：US20120250750A1

公开(公告)日：2012-10-04

申请号：US13435945

申请日：2012-03-30

申请人： Saurabh Mishra ,  Parag Naik ,  Subrahmanya Kondageri Shankaraiah ,  S. Harish Krishnan ,  Gururaj Padaki

发明人： Saurabh Mishra ,  Parag Naik ,  Subrahmanya Kondageri Shankaraiah ,  S. Harish Krishnan ,  Gururaj Padaki

IPC分类号： H04B17/00

CPC分类号： H04L27/0014 ,  H04L2027/003 ,  H04L2027/0065

摘要： A system and method for reducing implementation complexity for estimation of a Carrier Frequency Offset (CFO) and a Symbol Timing Offset (STO) for an input signal for spectrally shaped multiple communication standards. The system is implemented by replacing multiplier with shifters. The system includes a CFO estimation block, a STO estimation block, and a band extraction block that extracts a lower band edge and an upper band edge of the input signal. The STO estimation block includes (i) a sample error generation block that computes a sampling timing error value, and (ii) a Phase Lock Loop block that estimates a frequency error and a phase error corresponding to the sampling timing error value. The CFO estimation block includes (i) a carrier offset error generation block that generates a carrier offset error value, and (ii) a leaky average block for performing a filter operation.

摘要翻译： 用于降低用于频谱形状的多通信标准的输入信号的载波频偏（CFO）和符号定时偏移（STO）的实现复杂度的系统和方法。 该系统通过用移位器替换乘法器来实现。 该系统包括CFO估计块，STO估计块和提取输入信号的较低频带边沿和上边带边缘的频带提取块。 STO估计块包括（i）计算采样定时误差值的采样误差产生块，以及（ii）估计与采样定时误差值对应的频率误差和相位误差的锁相环块。 CFO估计块包括（i）产生载波偏移误差值的载波偏移误差产生块，和（ii）用于执行滤波操作的泄漏平均块。

公开(公告)号：US20080118006A1

公开(公告)日：2008-05-22

申请号：US11874337

申请日：2007-10-18

申请人： S. Harish Krishnan ,  Parag Naik

发明人： S. Harish Krishnan ,  Parag Naik

IPC分类号： H04L27/22

CPC分类号： H04L27/2662 ,  H04L27/2607 ,  H04L27/2665

摘要： At a receiver incoming coded OFDM Symbol Data are passed through a Coarse Symbol Timing Synchronization module to determine the approximate start of the symbol. In one embodiment this is accomplished through correlation. The symbol is then passed through an FFT (2K or 8K, depending on the mode desired by the receiver). Since the Coarse Symbol Timing Synchronization module only determines an approximate start point of the symbol, a process of fine synchronization is used to adjust this approximate start point and determine a more accurate start point of the symbol. In this manner, the receiver is enabled to process COFDM symbols in DVB-T transmissions (where the symbols include a cyclic prefix to overcome echoes). One output of an FFT operation is magnitude. Magnitude is used for Channel Estimation (or Channel Correction). Another output of an FFT operation is phase discontinuity or rotations. Phase discontinuities are used in a fine synchronization process to determine the number of phase discontinuities. Phase discontinuity data of the symbol is passed through an N-Point FFT.

摘要翻译： 在接收机输入的OFDM符号数据被传送通过粗符号定时同步模块来确定符号的大致开始。 在一个实施例中，这是通过相关来实现的。 然后，该符号通过FFT（2K或8K，取决于接收机所需的模式）。 由于粗符号定时同步模块仅确定符号的近似开始点，因此使用精细同步的过程来调整该近似起始点并确定符号的更准确的起始点。 以这种方式，接收机能够处理DVB-T传输中的COFDM符号（其中符号包括循环前缀以克服回声）。 FFT运算的一个输出是幅度。 幅度用于信道估计（或信道校正）。 FFT运算的另一个输出是相位不连续或旋转。 相位不连续性用于精细同步过程以确定相位不连续性的数量。 符号的相位不连续数据通过N点FFT。

公开(公告)号：US08605806B2

公开(公告)日：2013-12-10

申请号：US13436090

申请日：2012-03-30

申请人： S. Harish Krishnan ,  Shrinivas Bhat

发明人： S. Harish Krishnan ,  Shrinivas Bhat

IPC分类号： H04K1/10

CPC分类号： H04L27/2605 ,  H04L27/2663 ,  H04L27/2666 ,  H04L27/2678 ,  H04L27/2688

摘要： A receiver and method of detecting a guard interval estimate accurately by performing an Nth order polynomial based non-linear quantization on a pre-estimated guard interval in a received Orthogonal Frequency Division Multiplexing (OFDM) signal in a receiver is provided. The pre-estimated guard interval is obtained by performing normalized auto-correlation on the received OFDM signal. The method includes (i) performing a rounding operation on (a) one or more mth coefficient of the polynomial and (b) the pre-estimated guard interval to obtain an indexing parameter ‘k’, and detecting the guard interval estimate based on (i) a value of k, and (ii) a guard interval from one or more guard intervals that are stored in a look up table. The guard interval estimate is detected in accordance with an equation: {tilde over (L)}=L[k−4], where ‘L’ is the guard interval stored in the look up table that corresponds to the value of k.

摘要翻译： 提供了一种通过在接收机中接收到的正交频分复用（OFDM）信号中对预估的保护间隔执行基于N阶多项式的非线性量化来准确地检测保护间隔估计的接收机和方法。 通过对所接收的OFDM信号进行归一化的自相关来获得预估的保护间隔。 该方法包括：（i）对（a）多项式的一个或多个第m个系数和（b）预估的保护间隔执行舍入操作以获得索引参数'k'，并且基于（ i）值k，以及（ii）存储在查找表中的一个或多个保护间隔的保护间隔。 根据以下等式来检测保护间隔估计：{tilde over（L）} = L [k-4]，其中“L”是存储在查找表中对应于k的值的保护间隔。

公开(公告)号：US20120250807A1

公开(公告)日：2012-10-04

申请号：US13436090

申请日：2012-03-30

申请人： S. Harish Krishnan ,  Shrinivas Bhat

发明人： S. Harish Krishnan ,  Shrinivas Bhat

IPC分类号： H04L27/06

CPC分类号： H04L27/2605 ,  H04L27/2663 ,  H04L27/2666 ,  H04L27/2678 ,  H04L27/2688

摘要： A receiver and method of detecting a guard interval estimate accurately by performing an Nth order polynomial based non-linear quantization on a pre-estimated guard interval in a received Orthogonal Frequency Division Multiplexing (OFDM) signal in a receiver is provided. The pre-estimated guard interval is obtained by performing normalized auto-correlation on the received OFDM signal. The method includes (i) performing a rounding operation on (a) one or more mth coefficient of the polynomial and (b) the pre-estimated guard interval to obtain an indexing parameter ‘k’, and detecting the guard interval estimate based on (i) a value of k, and (ii) a guard interval from one or more guard intervals that are stored in a look up table. The guard interval estimate is detected in accordance with an equation: {tilde over (L)}=L[k−4], where ‘L’ is the guard interval stored in the look up table that corresponds to the value of k.

摘要翻译： 提供了一种通过在接收机中接收到的正交频分复用（OFDM）信号中对预估的保护间隔执行基于N阶多项式的非线性量化来准确地检测保护间隔估计的接收机和方法。 通过对所接收的OFDM信号进行归一化的自相关来获得预估的保护间隔。 该方法包括（i）对（a）多项式的一个或多个第m个系数和（b）预估保护间隔执行舍入运算以获得索引参数k，并且基于（i）检测保护间隔估计， k的值，以及（ii）存储在查询表中的一个或多个保护间隔的保护间隔。 根据以下等式来检测保护间隔估计：{tilde over（L）} = L [k-4]，其中L是存储在查找表中对应于k的值的保护间隔。