公开(公告)号：US07319660B2

公开(公告)日：2008-01-15

申请号：US10412262

申请日：2003-04-14

申请人： Ki-yun Kim ,  Ho Kim ,  Jun-yun Lee ,  Hyung-jin Choi

发明人： Ki-yun Kim ,  Ho Kim ,  Jun-yun Lee ,  Hyung-jin Choi

IPC分类号： H04J11/00

CPC分类号： H04L27/2613 ,  H04L27/2656

摘要： Provided is a frame synchronization pattern design and synchronization method by which in a transmitter of a communications system employing an orthogonal frequency division multiplexing (OFDM), a frame synchronization pattern is inserted into the starting part of a symbol frame, and by detecting the frame synchronization pattern in a receiver, synchronization of the OFDM transmitter and receiver is performed. Also, provided are a transmitter synchronization apparatus including an OFDM symbol frame generation unit, a frame synchronization pattern insertion unit, and an OFDM transmission signal conversion unit, and a receiver synchronization apparatus comprising a frame synchronization pattern inserted OFDM symbol frame conversion unit, a frame synchronization pattern detection unit, and a source data generation unit.Overcoming the conventional notion depending on the earlier art OFDM symbol standards, the OFDM symbol frame start detection method according to the present invention places a free-length code pattern, which is separately generated in a time domain, in the starting point of a frame and detects this pattern such that accuracy and efficiency greatly improve. Also, since the power value of a received signal is detected in the method, the communications system operates regardless of the frequency offset and phase offset. In addition, since a free-length pattern can be designed, the start point of a frame can be accurately detected in a seriously fading channel, by detecting a maximum peak based on correlation.

摘要翻译： 提供了一种帧同步模式设计和同步方法，在采用正交频分复用（OFDM）的通信系统的发射机中，将帧同步模式插入符号帧的起始部分，并通过检测帧同步 接收机中的模式，执行OFDM发射机和接收机的同步。 此外，提供了包括OFDM符号帧生成单元，帧同步码型插入单元和OFDM传输信号转换单元的发射机同步装置，以及包括帧同步码型插入OFDM符号帧转换单元的接收机同步装置， 同步模式检测单元和源数据生成单元。 根据本发明的OFDM符号帧起始检测方法克服了以前的OFDM符号标准的常规概念，将在时域中单独生成的自由长度码模式放在帧的起点处， 检测这种模式，使得精度和效率大大提高。 此外，由于在该方法中检测到接收信号的功率值，所以通信系统不管频率偏移和相位偏移如何运行。 此外，由于可以设计自由长度图案，因此通过基于相关性检测最大峰值，可以在严重衰落的信道中准确地检测帧的起始点。

公开(公告)号：US07554902B2

公开(公告)日：2009-06-30

申请号：US10420693

申请日：2003-04-23

申请人： Ki-yun Kim ,  Ho Kim ,  Hyung-jin Choi

发明人： Ki-yun Kim ,  Ho Kim ,  Hyung-jin Choi

IPC分类号： H04J11/00

CPC分类号： H04L27/2607 ,  H04L27/2657 ,  H04L27/2675

摘要： Provided is a transmission data frame in an orthogonal frequency division multiplexing (OFDM) burst mode transmission, and more particularly, a frequency offset estimating method and a channel equalizing method using a transmission data frame. In the transmission data frame used in the orthogonal frequency division multiplexing burst mode transmission, a length of a guard interval in a preamble area for frequency offset estimation and channel estimation varies depending on a channel environment not being limited in consideration of a size of a data symbol, and only data of ending part of the guard interval in the preamble is used to estimate frequency offset in consideration of intersymbol interference. In the frequency offset estimating method, desired frequency estimation efficiency can be satisfied with the small number of samples. Also, when channel equalization is performed, two symbols are averaged in a time area to reduce the accuracy of channel estimation due to Gaussian random noise. In a frequency area, by referring to weight placed on an adjacent subcarrier, a channel equalization coefficient is obtained to efficiently reduce Gaussian random noise.

摘要翻译： 提供了正交频分复用（OFDM）突发模式传输中的发送数据帧，更具体地，使用使用发送数据帧的频率偏移估计方法和信道均衡方法。 在正交频分复用突发模式传输中使用的发送数据帧中，用于频偏估计和信道估计的前同步码区域中的保护间隔的长度根据不受数据大小限制的信道环境而变化 符号，并且仅使用前导码中的保护间隔的结束部分的数据来估计考虑码间干扰的频率偏移。 在频率偏移估计方法中，可以利用少量样本来满足期望的频率估计效率。 此外，当执行信道均衡时，在时间区域中平均两个符号以降低由于高斯随机噪声导致的信道估计的准确度。 在频率区域中，通过参考相邻子载波上的权重，获得信道均衡系数以有效地降低高斯随机噪声。

公开(公告)号：US07321630B2

公开(公告)日：2008-01-22

申请号：US10692344

申请日：2003-10-24

申请人： Ki-yun Kim ,  Hyung-jin Choi ,  Ho Kim

发明人： Ki-yun Kim ,  Hyung-jin Choi ,  Ho Kim

IPC分类号： H04L27/28 ,  G06F1/02

CPC分类号： H04L27/2657 ,  H04L27/2679

摘要： An approximation method and system for series expansion of functions include the steps and functions, respectively, of: expanding an input function in Taylor series up to an (N−1)-th term; expanding the input function in Taylor series up to the N-th term; multiplying the expanded result up to the (N−1)-th term by a predetermined weight α; combining the expanded result up to the (N−1)-th term, multiplied by α, and the expanded result up to the N-th term; and dividing the combined result by (α+1).

摘要翻译： 函数串联扩展的近似方法和系统分别包括以下步骤和功能：将泰勒级数的输入函数扩展到第（N-1）项; 将泰勒系列中的输入函数扩展到第N个项; 将扩展结果乘以第（N-1）项预定权重α; 将扩展结果与第（N-1）项乘以α乘以扩展结果直到第N个项; 并将组合结果除以（α+ 1）。

公开(公告)号：US07505420B2

公开(公告)日：2009-03-17

申请号：US11151302

申请日：2005-06-14

申请人： Sang-hyun Do ,  Dong-kyu Kim ,  Hyung-jin Choi

发明人： Sang-hyun Do ,  Dong-kyu Kim ,  Hyung-jin Choi

IPC分类号： H04L12/26 ,  H04J3/06

CPC分类号： H04L27/2666 ,  H04L27/2665 ,  H04L27/2678 ,  H04N21/2383 ,  H04N21/4382

摘要： An apparatus for detecting a guard interval length (type) of a transmission symbol among the structure of an orthogonal frequency division multiplexing (OFDM) system receiver, to ensure proper operation of a symbol start detector and a fast Fourier transform (FFT) window position controller, is provided. This apparatus includes an analog-to-digital converter (ADC) for converting a received OFDM signal into digital complex samples, a symbol start position detector for detecting a symbol start position with reference to information on a guard interval length among the complex samples output by the ADC, a symbol start position difference detector for detecting the difference between the symbol start position detected by the symbol start position detector and a symbol start position delayed for a predetermined symbol time, a guard interval length detector for comparing the symbol start position difference detected by the symbol start position difference detector with a predetermined guard interval decision reference value and detecting the length of the guard interval, and an FFT window position controller for shifting the FFT window position using the guard interval length detected by the guard interval length detector and the symbol start information detected by the symbol start detector, to activate an FFT at the shifted FFT window position. The lengths of various guard intervals are automatically detected in the OFDM receiver, thus performing accurate FFT window recovery.

摘要翻译： 一种用于检测正交频分复用（OFDM）系统接收机的结构中的发送符号的保护间隔长度（类型）的装置，以确保符号起始检测器和快速傅里叶变换（FFT）窗口位置控制器的适当操作 ，被提供。 该装置包括用于将接收到的OFDM信号转换为数字复数样本的模数转换器（ADC），参考从由...输出的复样本中的保护间隔长度的信息来检测符号开始位置的符号开始位置检测器 ADC，用于检测由符号开始位置检测器检测的符号开始位置与延迟了预定符号时间的符号开始位置之间的差异的符号起始位置差异检测器，用于比较检测到的符号开始位置差异的保护间隔长度检测器 通过具有预定保护间隔决定参考值的符号开始位置差值检测器，并检测保护间隔的长度;以及FFT窗口位置控制器，用于使用由保护间隔长度检测器检测到的保护间隔长度来移位FFT窗口位置， 由符号开始检测器检测的符号开始信息 ，以便在移位的FFT窗口位置激活FFT。 在OFDM接收机中自动检测各种保护间隔的长度，从而执行精确的FFT窗口恢复。

公开(公告)号：US06798738B1

公开(公告)日：2004-09-28

申请号：US09509676

申请日：2000-07-25

申请人： Sang-hyun Do ,  Hyung-jin Choi ,  Hong-bae Cho

发明人： Sang-hyun Do ,  Hyung-jin Choi ,  Hong-bae Cho

IPC分类号： H04J1100

CPC分类号： H04L27/2665 ,  H04L27/2662 ,  H04N7/06

摘要： A fast Fourier transform (FFT) window position recovery apparatus in an orthogonal frequency division multiplexing (OFDM) receiver is provided. This apparatus, in an OFDM system receiver which receives an OFDM symbol comprised of a useful data interval and a guard interval and recovers a FFT window position, includes: an analog-to-digital converter (ADC) for converting a received OFDM signal into a digital complex sample; a symbol start detector for detecting a power difference between the digital complex samples output by the ADC and detecting a position having a minimum absolute value of the power difference between the samples, as a symbol starting position; and a FFT window controller for activating FFT by moving the FFT window position using symbol start information detected by the symbol start detector. The influence of frequency and phase offsets is reduced by using the power difference between adjacent samples delayed by the useful data interval, thus improving the reliability of a system.

摘要翻译： 提供了一种正交频分复用（OFDM）接收机中的快速傅里叶变换（FFT）窗口位置恢复装置。 该装置在接收包括有用数据间隔和保护间隔并恢复FFT窗口位置的OFDM符号的OFDM系统接收机中包括：模数转换器（ADC），用于将接收的OFDM信号转换为 数字复杂样本; 符号起始检测器，用于检测由ADC输出的数字复样本之间的功率差，并检测具有样本之间的功率差的最小绝对值的位置作为符号开始位置; 以及FFT窗口控制器，用于通过使用由符号开始检测器检测的符号开始信息移动FFT窗口位置来激活FFT。 通过使用延迟有用数据间隔的相邻采样之间的功率差来降低频率和相位偏移的影响，从而提高系统的可靠性。

公开(公告)号：US20100124382A1

公开(公告)日：2010-05-20

申请号：US12507491

申请日：2009-07-22

申请人： Hyung-jin Choi

发明人： Hyung-jin Choi

IPC分类号： G06K9/42

CPC分类号： H04N5/2622 ,  H04N5/21

摘要： A display apparatus and a displaying method thereof are provided. The display apparatus includes image quality improvement unit which performs image quality improvement with respect to video signals, a display unit which displays general video signals and video signals of which image quality is improved by the image quality improvement unit, and a control unit which controls the display unit to move a boundary between a first area on which the general video signals are displayed and a second area on which the video signals of improved image quality are displayed in a specific pattern. Accordingly, the boundary between the first area to which image quality improvement is not applied and the second area to which image quality improvement is applied is movable so that the display apparatus can stimulate the customer's buying interests.

摘要翻译： 提供了一种显示装置及其显示方法。 显示装置包括对于视频信号进行图像质量改善的图像质量改善单元，显示通过图像质量改进单元改善图像质量的一般视频信号和视频信号的显示单元，以及控制单元 显示单元，用于移动在其上显示一般视频信号的第一区域和其上以特定模式显示改进的图像质量的视频信号的第二区域之间的边界。 因此，不施加图像质量改善的第一区域和应用图像质量改善的第二区域之间的边界是可移动的，使得显示装置可以刺激顾客的购买兴趣。

公开(公告)号：US06853616B1

公开(公告)日：2005-02-08

申请号：US09555046

申请日：1998-11-24

申请人： Dong-kyu Kim ,  Sang-hyun Do ,  Hyung-jin Choi

发明人： Dong-kyu Kim ,  Sang-hyun Do ,  Hyung-jin Choi

IPC分类号： H04J11/00 ,  H04B3/04 ,  H04L27/26

CPC分类号： H04L27/2665 ,  H04L27/2662

摘要： An OFDM receiver for interlocking FFT window position recovery with sampling clock control, and a method thereof are provided. This method includes the steps of: extracting a pilot signal from fast-Fourier-transformed OFDM received signals, and detecting inter-pilot phase differences; averaging the detected phase differences for a symbol and normalizing the mean phase difference by dividing it into reference values corresponding to phase differences generated when FFT window errors of at least one sample exist; and simultaneously controlling the FFT window position offset using a value obtained by rounding off the normalized value, and the sampling clock offset using the difference between the round-off value and the normalized value.

摘要翻译： 提供了一种用于使FFT窗口位置恢复与采样时钟控制互锁的OFDM接收器及其方法。 该方法包括以下步骤：从快速傅里叶变换的OFDM接收信号中提取导频信号，并检测导频间的相位差; 对于符号的检测到的相位差进行平均，并将平均相位差归一化，将其分成对应于存在至少一个样本的FFT窗口误差时产生的相位差的参考值; 并且使用通过舍入归一化值而获得的值以及使用舍入值与归一化值之间的差来采样时钟偏移来同时控制FFT窗口位置偏移。

公开(公告)号：US07295715B2

公开(公告)日：2007-11-13

申请号：US10617798

申请日：2003-07-14

申请人： Byoung-hwa Jung ,  Hyung-jin Choi

发明人： Byoung-hwa Jung ,  Hyung-jin Choi

IPC分类号： G06K9/40

CPC分类号： G06T5/002 ,  G06T5/003 ,  G06T5/10 ,  G06T2207/20056

摘要： Provided are an apparatus and method for precisely processing an input signal by detecting the frequency characteristic of the signal and applying the detection result in an image signal processing block to reduce noise in the signal or enhance the details of the signal. The apparatus includes an indication value calculator, a level selector, and a frequency characteristic determination unit. Accordingly, the frequency distribution of an input signal is analyzed, and the signal is filtered by adjusting its filtering frequency band based on the analyzed frequency characteristic. Thus, it is possible to appropriately filter a signal using only a filter regardless of the resolution of the signal. In particular, noise in the signals of different scale ratios can be reduced or the details of the signal can be enhanced by processing the signals by only a filter.

摘要翻译： 提供了一种通过检测信号的频率特性并将检测结果应用于图像信号处理块来精确地处理输入信号的装置和方法，以减少信号中的噪声或增强信号的细节。 该装置包括指示值计算器，电平选择器和频率特性确定单元。 因此，分析输入信号的频率分布，并且通过基于所分析的频率特性调整其滤波频带来对信号进行滤波。 因此，无论信号的分辨率如何，都可以仅使用滤波器适当地滤波信号。 特别地，可以减小不同比例尺的信号中的噪声，或者可以通过仅通过滤波器处理信号来增强信号的细节。

公开(公告)号：US20070047647A1

公开(公告)日：2007-03-01

申请号：US11507468

申请日：2006-08-22

申请人： Ki-deok Lee ,  Seung-joon Yang ,  Young-ho Lee ,  Hak-hun Choi ,  Hyung-jin Choi

发明人： Ki-deok Lee ,  Seung-joon Yang ,  Young-ho Lee ,  Hak-hun Choi ,  Hyung-jin Choi

IPC分类号： H04N7/12 ,  H04B1/66

CPC分类号： H04N5/208 ,  G06T5/002 ,  G06T5/003 ,  G06T5/20 ,  G06T7/20 ,  G06T2207/20012 ,  H04N5/145

摘要： An image enhancement apparatus using motion estimation includes: a motion estimation unit estimating a degree of motion between an input image on which image enhancement is performed and a temporally successive image; and an enhancement unit applying the image enhancement to an area without motion in the input image while not applying the image enhancement to an area with motion in the input image on the basis of the motion degree. Accordingly, by performing image enhancement on an area without motion in an input image while not performing image enhancement on an area with motion in the input image, it is possible to prevent image noise from being generated in the area with motion.

摘要翻译： 使用运动估计的图像增强装置包括：运动估计单元，估计在其上执行图像增强的输入图像与时间上连续的图像之间的运动程度; 以及增强单元，其基于所述运动程度，在不输入所述输入图像中的运动区域的情况下，将所述图像增强应用于所述输入图像中的运动区域。 因此，通过在输入图像中对运动区域进行图像增强的同时对输入图像中的运动区域进行图像增强，可以防止在运动区域产生图像噪声。

公开(公告)号：US20050232217A1

公开(公告)日：2005-10-20

申请号：US11151302

申请日：2005-06-14

申请人： Sang-hyun Do ,  Dong-kyu Kim ,  Hyung-jin Choi

发明人： Sang-hyun Do ,  Dong-kyu Kim ,  Hyung-jin Choi

IPC分类号： H04J11/00 ,  H04J1/05 ,  H04L27/26 ,  H04N7/24 ,  H04J1/00

CPC分类号： H04L27/2666 ,  H04L27/2665 ,  H04L27/2678 ,  H04N21/2383 ,  H04N21/4382

摘要： An apparatus for detecting a guard interval length (type) of a transmission symbol among the structure of an orthogonal frequency division multiplexing (OFDM) system receiver, to ensure proper operation of a symbol start detector and a fast Fourier transform (FFT) window position controller, is provided. This apparatus includes an analog-to-digital converter (ADC) for converting a received OFDM signal into digital complex samples, a symbol start position detector for detecting a symbol start position with reference to information on a guard interval length among the complex samples output by the ADC, a symbol start position difference detector for detecting the difference between the symbol start position detected by the symbol start position detector and a symbol start position delayed for a predetermined symbol time, a guard interval length detector for comparing the symbol start position difference detected by the symbol start position difference detector with a predetermined guard interval decision reference value and detecting the length of the guard interval, and an FFT window position controller for shifting the FFT window position using the guard interval length detected by the guard interval length detector and the symbol start information detected by the symbol start detector, to activate an FFT at the shifted FFT window position. The lengths of various guard intervals are automatically detected in the OFDM receiver, thus performing accurate FFT window recovery.