-
公开(公告)号：US07440506B2
公开(公告)日：2008-10-21
申请号：US11088310
申请日：2005-03-24
IPC分类号： H04L27/28
CPC分类号： H04L25/03159 , H04L5/0048 , H04L25/0216 , H04L25/0222 , H04L25/0232 , H04L27/2665
摘要： A receiver for recovering data from a received symbol of signal samples generated in accordance with Orthogonal Frequency Division Multiplexing (OFDM), the OFDM symbol including pilot carrier signals, the receiver including a pilot assisted channel estimator comprising a pilot extractor configured to extract the pilot carrier signals from the signal samples, and to generate an estimate of a sample of a channel frequency response for each of the pilot carrier signals in the received OFDM symbol, by comparing the extracted pilot carrier signals with predetermined versions of the pilot carrier signals, and a frequency interpolation filter configured to interpolate the samples of the channel frequency response estimate, and a filter controller, the frequency response of the frequency interpolation filter including a pass bandwidth which is adjustable, and the filter controller configured to adjust the bandwidth of the frequency interpolation filter to reduce noise in the estimate of channel frequency response.
摘要翻译： 一种接收机，用于从接收到的符合正交频分复用（OFDM）的信号样本的符号恢复数据，所述OFDM符号包括导频载波信号，所述接收机包括导频辅助信道估计器，导频辅助信道估计器包括导频提取器，导频提取器被配置为提取导频载波 信号，并且通过将所提取的导频载波信号与导频载波信号的预定版本进行比较来生成对接收的OFDM符号中的每个导频载波信号的信道频率响应的采样的估计，以及 频率内插滤波器，被配置为内插频道频率响应估计的样本，以及滤波器控制器，频率插值滤波器的频率响应包括可调整的通带宽度，并且滤波器控制器被配置为调整频率插值滤波器的带宽 以减少通道估计中的噪声 l频率响应。
-
公开(公告)号：US20070070882A1
公开(公告)日：2007-03-29
申请号：US11489161
申请日：2006-07-19
申请人： Hidetoshi Kawauchi , Toshihisa Hyakudai , Takuya Okamoto , Atsushi Yajima , Taku Yamagata , Kazutaka Yamamoto , Shigenari Kawabata
发明人： Hidetoshi Kawauchi , Toshihisa Hyakudai , Takuya Okamoto , Atsushi Yajima , Taku Yamagata , Kazutaka Yamamoto , Shigenari Kawabata
IPC分类号： H04J11/00
CPC分类号： H04L25/0232 , H04L27/261 , H04L27/265 , H04L27/2662 , H04L27/2665
摘要： An orthogonal frequency division multiplexing (OFDM) demodulating apparatus includes a delay profile creating section, a Fourier converting section, a pilot signal extracting section, a transmission path characteristic estimating section, an inverse Fourier converting section, and a window control section. In this case, the window control section creates a delay profile for defining a calculation range by leaving a path which exists at a same position in both the delay profiles created by the delay profile creating section and the inverse Fourier converting section and the number of times of detection which is equal to or higher than a threshold value and defines a higher threshold value for the path at a predetermined position from the position of the main path within the delay profile created by the inverse Fourier converting section than for the paths at the other positions.
摘要翻译： 正交频分复用（OFDM）解调装置包括延迟分布创建部分，傅里叶变换部分，导频信号提取部分，传输路径特性估计部分，傅里叶逆变换部分和窗口控制部分。 在这种情况下，窗口控制部分通过在由延迟分布创建部分和逆傅里叶变换部分创建的两个延迟分布中的相同位置处留下一条路径和次数来创建用于定义计算范围的延迟分布 检测值等于或高于阈值，并且在从由傅立叶逆变换部分创建的延迟分布内的主路径的位置处的预定位置处的路径定义更高的阈值，而不是在另一个路径 职位
-
公开(公告)号：US08406322B2
公开(公告)日：2013-03-26
申请号：US12278709
申请日：2007-02-06
申请人： Takuya Okamoto , Taku Yamagata , Takahiro Okada
发明人： Takuya Okamoto , Taku Yamagata , Takahiro Okada
IPC分类号： H04L27/28
CPC分类号： H04L27/2657 , H04L5/0007 , H04L5/0048 , H04L27/261 , H04L27/2675
摘要： An orthogonal frequency division multiplexed (OFDM) demodulation device for demodulating an OFDM signal is disclosed. The device includes a means that demodulates the OFDM signal to produce a baseband OFDM signal. The device also includes a means that detects a carrier frequency offset amount that is a shift amount of a center frequency of the baseband OFDM signal, based on correlation of subcarriers to which a predetermined signal is inserted. Additionally, the device includes a means that controls a frequency of the carrier signal depending on the carrier frequency offset amount. The means that detects the carrier frequency offset amount divides subcarriers into a plurality of groups, calculates a correlation value with respect to an adjacent transmission symbol for each of the groups, adds the correlation values to each other for all the groups, and defines an offset amount assumed when a maximum addition-result value is obtained as the carrier frequency offset amount.
摘要翻译： 公开了一种用于解调OFDM信号的正交频分复用（OFDM）解调装置。 该装置包括解调OFDM信号以产生基带OFDM信号的装置。 该装置还包括基于插入了预定信号的子载波的相关性来检测作为基带OFDM信号的中心频率的移位量的载波频率偏移量的装置。 另外，该装置包括根据载波频率偏移量来控制载波信号的频率的装置。 检测载波频率偏移量的装置将副载波分成多个组，针对每个组计算相对于相邻传输符号的相关值，将所有组的相关值相加，并且定义偏移量 当获得最大相加结果值作为载波频率偏移量时，假定该量。
-
公开(公告)号：US07889802B2
公开(公告)日：2011-02-15
申请号：US11908874
申请日：2007-02-06
IPC分类号： H04L27/28
CPC分类号： H04N5/455 , H04L27/22 , H04L27/2647 , H04L27/38 , H04N5/211 , H04N21/4382
摘要： A demodulator includes a complex conjugate signal generator to generate a complex conjugate signal of an OFDM time domain signal (complex signal including an I channel signal and Q channel signal) supplied from an orthogonal demodulation circuit, a delaying unit to delay, by an integral multiple of a predetermined period 1H or 2H, the complex conjugate signal supplied from the complex conjugate signal generator, a complex multiplier to make complex multiplication on the basis of the complex signal generated by the orthogonal demodulation circuit and complex conjugate signal delayed by the integral multiple of the predetermined period by the delay unit, and a determining unit to determine whether an interference wave is included in the modulated signal by making a comparison between the complex multiplication value resulted from the complex multiplication made by the complex multiplier and an arbitrary threshold.
摘要翻译： 解调器包括复共轭信号发生器，用于产生从正交解调电路提供的OFDM时域信号（包括I信道信号和Q信道信号的复信号）的复共轭信号，延迟单元以整数倍 从复共轭信号发生器提供的复共轭信号，复数乘法器，根据由正交解调电路产生的复信号和复数共轭信号进行复乘以延迟整数倍的整数倍 所述延迟单元的所述预定周期，以及确定单元，通过对由所述复数乘法器产生的复乘产生的复数乘法值与任意阈值进行比较，来确定所述调制信号中是否包含干扰波。
-
公开(公告)号：US07388922B2
公开(公告)日：2008-06-17
申请号：US11087317
申请日：2005-03-23
申请人： Taku Yamagata
发明人： Taku Yamagata
IPC分类号： H04K1/10
CPC分类号： H04L25/0234 , H04L5/0048 , H04L25/022 , H04L25/0222 , H04L27/2665
摘要： A receiver for recovering data from a received symbol of signal samples generated in accordance with Orthogonal Frequency Division Multiplexing (OFDM) includes a pilot assisted channel estimator operable to generate an estimate of a transmission channel through which the received OFDM symbol has passed. The OFDM symbol includes pilot signals provided at different sub-carrier locations for each of a set of OFDM symbols, the sub-carrier locations of the pilot signals being repeated for subsequent sets of symbols. The pilot assisted channel estimator includes a pilot extractor, a time interpolation filter controller and an adaptive bandwidth interpolation filter.
摘要翻译： 用于从根据正交频分复用（OFDM）生成的信号样本的接收符号恢复数据的接收机包括导频辅助信道估计器，用于产生接收到的OFDM符号经过的传输信道的估计。 OFDM符号包括为一组OFDM符号中的每一个而在不同的子载波位置处提供的导频信号，导频信号的子载波位置被重复用于随后的符号集合。 导频辅助信道估计器包括导频提取器，时间插值滤波器控制器和自适应带宽插值滤波器。
-
6.发明授权公开(公告)号：US06996193B2
公开(公告)日：2006-02-07
申请号：US09771743
申请日：2001-01-29
申请人： Taku Yamagata , Shunji Maeda
发明人： Taku Yamagata , Shunji Maeda
IPC分类号： H04L27/22
CPC分类号： H04L7/0054 , H03D3/22 , H04L27/2273 , H04L2027/0036 , H04L2027/0057
摘要： A timing error detection circuit capable of detecting a timing error of symbols in a signal with a simple and small-sized configuration, comprising a sampling circuit for sampling a signal including symbols arranged at a predetermined symbol cycle at a frequency equal to four times of a symbol rate, an amplitude detection circuit for detecting an amplitude of a position subjected to said sampling in said signal, a difference detection circuit for detecting a timing error indicating deviation of the symbol included in the signal from a conceivable timing based on difference of said detected plurality of amplitudes, and a timing error signal generation circuit.
摘要翻译： 一种定时误差检测电路，能够检测具有简单和小尺寸配置的信号中的符号的定时误差，该电路包括采样电路，该采样电路包括以等于四倍的频率的预定符号周期排列的符号 符号率，用于检测在所述信号中进行所述采样的位置的振幅的幅度检测电路;差分检测电路，用于根据所检测到的差异检测指示包括在信号中的符号与可设想的定时的偏差的定时误差 多个振幅，以及定时误差信号发生电路。
-
公开(公告)号：US06587503B1
公开(公告)日：2003-07-01
申请号：US09455245
申请日：1999-12-06
IPC分类号： H04B1700
CPC分类号： H04B7/18523
摘要： An information processing apparatus in which an eye center measuring unit determines a code judgment point from a peak timing signal supplied from a timing signal generation circuit and an amplitude signal supplied from an interpolator and detected by an amplitude detector, and outputs it to a multiplier via an amplifier, a subtracter, and a reciprocal generating unit. A zero cross point measuring unit determines a code change point from a zero cross timing signal supplied from a timing signal generation circuit and an amplitude signal supplied from the interpolator and detected by the amplitude detector, and outputs it to the multiplier via a subtracter. The multiplier multiplies the supplied signals, and a dB converter converts a supplied signal into a signal in decibels and outputs the signal to a display circuit.
摘要翻译： 一种信息处理装置，其中眼睛中心测量单元根据从定时信号产生电路提供的峰值定时信号和由内插器提供并由振幅检测器检测的振幅信号来确定码判断点，并通过振幅检测器将其输出到乘法器 放大器，减法器和互逆生成单元。 零交叉点测量单元从由定时信号发生电路提供的零交叉定时信号和从内插器提供并由幅度检测器检测的振幅信号确定代码变化点，并通过减法器将其输出到乘法器。 乘法器将所提供的信号相乘，并且dB转换器将提供的信号转换成分贝的信号，并将该信号输出到显示电路。
-
公开(公告)号：US20050213680A1
公开(公告)日：2005-09-29
申请号：US11088310
申请日：2005-03-24
申请人： Samuel Atungsiri , Taku Yamagata
发明人： Samuel Atungsiri , Taku Yamagata
CPC分类号： H04L25/03159 , H04L5/0048 , H04L25/0216 , H04L25/0222 , H04L25/0232 , H04L27/2665
摘要： A receiver for recovering data from a symbol of signal samples generated in accordance with Orthogonal Frequency Division Multiplexing is described. The symbol may be a COFDM symbol in accordance with the DVB-T standard, and includes pilot carrier signals for use in estimating channel conditions. The receiver includes a pilot assisted channel estimator comprising a pilot extractor operable to extract the pilot carrier signals from the signal samples and to generate from the extracted pilots samples of the channel frequency response or channel transfer function estimate. The channel frequency response generator is operable to compare the extracted pilot carrier signals with a predetermined version of the pilot carrier signals. The pilot assisted channel estimator includes a frequency dimension interpolation filter operable to interpolate the pilot-derived samples of the channel frequency response in the frequency dimension, and a filter controller. The frequency response of the frequency interpolation filter has a pass bandwidth, which is adjustable, and the filter controller is operable to adjust the bandwidth of the frequency interpolation filter to the effect of reducing noise in the channel frequency response estimate. The use of an adjustable pass bandwidth for a frequency domain interpolation filter can advantageously be used to reduce noise in the channel impulse response estimate by enabling an appropriate selection of the bandwidth of the frequency domain interpolation filter according to the particular current characteristics of the channel impulse response.
摘要翻译： 描述了从根据正交频分复用产生的信号样本的符号恢复数据的接收机。 符号可以是根据DVB-T标准的COFDM符号，并且包括用于估计信道条件的导频载波信号。 接收机包括导频辅助信道估计器，其包括导频提取器，其可操作以从信号样本中提取导频载波信号，并从提取的导频生成信道频率响应或信道传输函数估计的样本。 信道频率响应发生器可操作以将提取的导频载波信号与导频载波信号的预定版本进行比较。 导频辅助信道估计器包括可用于内插频率维度中的信道频率响应的导频导出采样的频率维插值滤波器和滤波器控制器。 频率插值滤波器的频率响应具有可调整的通带宽度，滤波器控制器可操作地调整频率插值滤波器的带宽以减少信道频率响应估计中的噪声。 可以有利地使用用于频域内插滤波器的可调节通带宽度来通过根据信道脉冲的特定电流特性来适当地选择频域内插滤波器的带宽来减少信道脉冲响应估计中的噪声 响应。
-
公开(公告)号：US20050213679A1
公开(公告)日：2005-09-29
申请号：US11087317
申请日：2005-03-23
申请人： Taku Yamagata
发明人： Taku Yamagata
CPC分类号： H04L25/0234 , H04L5/0048 , H04L25/022 , H04L25/0222 , H04L27/2665
摘要： A receiver for recovering data from a received symbol of signal samples generated in accordance with Orthogonal Frequency Division Multiplexing (OFDM) includes a pilot assisted channel estimator operable to generate an estimate of a transmission channel through which the received OFDM symbol has passed. The OFDM symbol includes pilot signals provided at different sub-carrier locations for each of a set of OFDM symbols, the sub-carrier locations of the pilot signals being repeated for subsequent sets of symbols. The pilot assisted channel estimator comprises a pilot extractor, a time interpolation filter controller and an adaptive bandwidth interpolation filter. The channel assisted channel estimator is operable to extract the pilot carrier signals from the signal samples, and to generate an estimate of a sample of the channel frequency response for each pilot signal in the received OFDM symbol, by comparing the extracted pilot carrier signals with predetermined versions of the pilot carriers. The adaptive bandwidth time interpolation filter is operable to interpolate the samples of the channel frequency response derived from pilot carrier signals at corresponding sub-carrier locations within temporally separated OFDM symbols to generate an interpolated version of the channel frequency response estimate. The time interpolation filter controller is operable to generate an estimate of a rate of change of the channel frequency response with time and to adapt a pass bandwidth of the time interpolation filter in accordance with the determined rate of change of the channel. As such, there is an increased likelihood of correctly recovering data conveyed by the OFDM symbol.
摘要翻译： 用于从根据正交频分复用（OFDM）生成的信号样本的接收符号恢复数据的接收机包括导频辅助信道估计器，用于产生接收到的OFDM符号经过的传输信道的估计。 OFDM符号包括为一组OFDM符号中的每一个而在不同的子载波位置处提供的导频信号，导频信号的子载波位置被重复用于随后的符号集合。 导频辅助信道估计器包括导频提取器，时间插值滤波器控制器和自适应带宽插值滤波器。 信道辅助信道估计器可操作以从信号样本中提取导频载波信号，并且通过将提取的导频载波信号与预定的导频载波信号进行比较来产生对接收到的OFDM符号中的每个导频信号的信道频率响应样本的估计 试点运营商的版本。 自适应带宽时间内插滤波器可用于内插在时间上分离的OFDM符号内的相应子载波位置处从导频载波信号导出的信道频率响应的样本，以产生信道频率响应估计的内插版本。 时间插值滤波器控制器可操作以随时间产生信道频率响应的变化率的估计，并且根据所确定的信道变化率来适应时间插值滤波器的通带宽度。 因此，正确地恢复由OFDM符号传送的数据的可能性增加。
-
公开(公告)号：US07701841B2
公开(公告)日：2010-04-20
申请号：US11489161
申请日：2006-07-19
申请人： Hidetoshi Kawauchi , Toshihisa Hyakudai , Takuya Okamoto , Atsushi Yajima , Taku Yamagata , Kazutaka Yamamoto , Shigenari Kawabata
发明人： Hidetoshi Kawauchi , Toshihisa Hyakudai , Takuya Okamoto , Atsushi Yajima , Taku Yamagata , Kazutaka Yamamoto , Shigenari Kawabata
IPC分类号： H04J11/00
CPC分类号： H04L25/0232 , H04L27/261 , H04L27/265 , H04L27/2662 , H04L27/2665
摘要： An orthogonal frequency division multiplexing (OFDM) demodulating apparatus includes a delay profile creating section, a Fourier converting section, a pilot signal extracting section, a transmission path characteristic estimating section, an inverse Fourier converting section, and a window control section. In this case, the window control section creates a delay profile for defining a calculation range by leaving a path which exists at a same position in both the delay profiles created by the delay profile creating section and the inverse Fourier converting section and the number of times of detection which is equal to or higher than a threshold value and defines a higher threshold value for the path at a predetermined position from the position of the main path within the delay profile created by the inverse Fourier converting section than for the paths at the other positions.
摘要翻译： 正交频分复用（OFDM）解调装置包括延迟分布创建部分，傅里叶变换部分，导频信号提取部分，传输路径特性估计部分，傅里叶逆变换部分和窗口控制部分。 在这种情况下，窗口控制部分通过在由延迟分布形成部分和逆傅里叶变换部分创建的两个延迟分布中的相同位置处留下一条路径和次数来创建用于定义计算范围的延迟分布 检测值等于或高于阈值，并且在由傅里叶逆变换部分创建的延迟分布内的主路径的位置处的预定位置处的路径定义更高的阈值，而不是在另一个路径 职位
-
-
-
-
-
-
-
-
-
搜索结果
13 条记录 (耗时 0.041 秒)