公开(公告)号：US06983028B2

公开(公告)日：2006-01-03

申请号：US09934693

申请日：2001-08-23

申请人： Keun Hee Ahn

发明人： Keun Hee Ahn

IPC分类号： H04L27/38 ,  H04B1/10

CPC分类号： H04L27/2273 ,  H04L2027/003 ,  H04L2027/0057 ,  H04L2027/0065 ,  H04L2027/0067

摘要： A carrier restoration apparatus for acquiring a frequency offset and tracking a phase jitter from a pass-band digital signal having the frequency offset and the phase jitter is disclosed. In the apparatus, a frequency acquisition PLL section for acquiring the frequency offset and a phase tracking PLL section for tracking the residual phase jitter are separately constructed, and the apparatus operates in two modes for first acquiring the frequency offset and then tracking the residual phase jitter. Thus, a rapid acquisition/tracking is performed so as to minimize the frequency offset and phase jitter of several hundred KHz produced from a tuner or an RF oscillator, and a high-reliability acquisition/tracking can be performed even under the low SNR and serious channel ISI (i.e., ghost).

公开(公告)号：US06980609B1

公开(公告)日：2005-12-27

申请号：US09645437

申请日：2000-08-25

申请人： Keun Hee Ahn

发明人： Keun Hee Ahn

IPC分类号： H04N7/015 ,  H03D1/00 ,  H04L27/00 ,  H04L27/06

CPC分类号： H04L27/06 ,  H04L2027/003 ,  H04L2027/0042 ,  H04L2027/0057 ,  H04L2027/0063

摘要： A digital passband matched filter is automatically adapted to a carrier wave ω in accordance with a frequency offset of the carrier wave, to obtain a passband digital signal having no frequency distortion due to the frequency offset. Thus, a receiver in which drawbacks such as decrease of SNR and increase of circuit complexity caused by the fixed baseband/passband matched filter is obtained. Since a cosine wave generating section operates in a carrier wave frequency restoring mode and a carrier wave frequency adaptive mode, respectively, a single cosine wave ROM table can be used regardless of the respective operating modes, thereby reducing circuit complexity. Since the digital passband matched filter acts to renew the filter coefficients adapted to the carrier wave adaptive mode only, power consumption required to operate the filter can be minimized.

摘要翻译： 根据载波的频率偏移，数字通带匹配滤波器自动地适应于载波ω，从而获得由于频率偏移而没有频率失真的通带数字信号。 因此，获得了诸如SNR的降低和由固定基带/通带匹配滤波器引起的电路复杂度增加的缺点的接收机。 由于余弦波生成部分分别以载波频率恢复模式和载波频率自适应模式工作，所以可以使用单个余弦波ROM表，而不管各自的工作模式如何，从而降低电路复杂度。 由于数字通带匹配滤波器仅用于更新适合于载波自适应模式的滤波器系数，因此可以最小化操作滤波器所需的功耗。

公开(公告)号：US07221715B2

公开(公告)日：2007-05-22

申请号：US10372217

申请日：2003-02-25

申请人： Keun Hee Ahn

发明人： Keun Hee Ahn

IPC分类号： H04L25/49 ,  H04L27/00 ,  H03D3/24

CPC分类号： H04N21/4305 ,  H03L7/091 ,  H04L7/0334 ,  H04L7/0335

摘要： Timing recovery device for recovering a symbol clock from a received broadcasting signal, wherein a sign is used as a timing error, which is extracted from a result of multiplication of a difference of two symbol samples and an intermediate sample thereof, thereby very great average gain with respect to the timing error, that shortens a time period required for capturing the timing error. Particularly, since the very great average gain is obtainable even in a case a 0 dB presents, the timing offset can be captured at a short time period.

摘要翻译： 定时恢复装置，用于从接收到的广播信号中恢复符号时钟，其中使用符号作为定时误差，其从两个符号样本的差和其中间样本的乘积的结果中提取，从而获得非常大的平均增益 相对于定时误差，缩短了捕获定时误差所需的时间段。 特别是，即使在出现0dB的情况下也可获得非常大的平均增益，所以可以在短时间段内捕获定时偏移。

公开(公告)号：US06671339B1

公开(公告)日：2003-12-30

申请号：US09615716

申请日：2000-07-13

申请人： Keun Hee Ahn

发明人： Keun Hee Ahn

IPC分类号： H03K501

CPC分类号： H03L7/095 ,  H04L27/3827 ,  H04L2025/03547 ,  H04L2027/0038

摘要： A lock detecting apparatus for a multimedia digital broadcasting receiver is disclosed. The present invention is a general purpose lock detecting apparatus applicable to a channel equalizer as well as a carrier recovery unit. Also, the present lock detecting apparatus uses two lock threshold values throughout a pull-in and lock-in, to improve the reliability of the lock detector for a false lock.

摘要翻译： 公开了一种用于多媒体数字广播接收机的锁定检测装置。 本发明是适用于信道均衡器以及载波恢复单元的通用锁定检测装置。 此外，本锁定检测装置在整个拉入和锁定期间使用两个锁定阈值，以提高锁定检测器的假锁的可靠性。

公开(公告)号：US07505514B2

公开(公告)日：2009-03-17

申请号：US11002806

申请日：2004-12-01

申请人： Keun Hee Ahn

发明人： Keun Hee Ahn

IPC分类号： H03H7/30 ,  G06F17/10

CPC分类号： H04H40/18 ,  H04L25/03057 ,  H04L2025/03382 ,  H04L2025/03401 ,  H04L2025/0342 ,  H04L2025/0349 ,  H04L2027/003 ,  H04N5/211

摘要： There are provided a phase-compensation decision feedback channel equalizer. The phase-compensation decision feedback channel equalizer equalizes phases of signals outputted from a feedforward filter and a feedback filter regardless of a phase distorted by a carrier wave and a ghost, thereby satisfying the same ghost removal performance.

摘要翻译： 提供了相位补偿判决反馈信道均衡器。 相位补偿判定反馈信道均衡器对从前馈滤波器和反馈滤波器输出的信号的相位进行均衡，而不管由载波和重影失真的相位如何，从而满足相同的重影去除性能。

公开(公告)号：US06826238B2

公开(公告)日：2004-11-30

申请号：US09741049

申请日：2000-12-21

申请人： Keun Hee Ahn

发明人： Keun Hee Ahn

IPC分类号： H04L2714

CPC分类号： H04L27/0014 ,  H04L27/3818 ,  H04L2027/0028 ,  H04L2027/0053 ,  H04L2027/0057 ,  H04L2027/0067

摘要： Disclosed is a quadrature amplitude modulation (QAM) receiver and a carrier recovery method which receive a signal modulated by the QAM method and recover the frequency offset and phase jitter of the carrier particularly using a weighted phase error inversely proportionate to the magnitude of the deciding signal character, as a result of which the phase jitter of the demodulated signal characters is constant in size irrespective of the magnitude of the deciding signal character. Consequently, acquisition/tracking can be rapidly achieved to minimize the frequency offset of several hundreds of KHz and the phase jitter generated from a tuner or an RF oscillator.

摘要翻译： 公开了正交幅度调制（QAM）接收机和载波恢复方法，其接收由QAM方法调制的信号，并且特别地使用与决定信号的幅度成反比的加权相位误差来恢复载波的频偏和相位抖动 因此，解调信号字符的相位抖动在大小上是恒定的，与决定信号字符的大小无关。 因此，可以快速实现采集/跟踪以最小化数百KHz的频率偏移和从调谐器或RF振荡器产生的相位抖动。