公开(公告)号：US06771719B1

公开(公告)日：2004-08-03

申请号：US09510236

申请日：2000-02-22

申请人： Takeshi Koyama ,  Takashi Seki ,  Noboru Taga

发明人： Takeshi Koyama ,  Takashi Seki ,  Noboru Taga

IPC分类号： H04L2708

CPC分类号： H03G3/3068

摘要： The automatic gain control method with little being influenced of the unnecessary electric wave, even if strong unnecessary electric wave is near the frequency of input signal, is offered by carrying out change of the delay point level. The automatic gain control system with a scale of few circuit, having low noise property and high adjacent disturbance oppression property, is offered. When the IF AGC signal 112 is smaller than delay point level, the output agcerr of the signal level detector 614 is provided to the 1st loop filter 105. Since the IF AGC signal 112 provided to the IF AGC amplifier 608 is value responding to signal level of IF signal, output is fed back to this amplifier, and control of IF gain is performed automatically. On the other hand, when output of the 2nd loop filter 106 is “0”, output rfzero of the 2nd comparator 108 is set to 1, and “0” is provided to the 2nd loop filter 106. When the output of the 2nd loop filter 106 is not “0”, it is set to “0”, fixed value-rfdump is provided to the 2nd loop filter 106, and the output of the 2nd comparator 108 is converged when output of this loop filter became “0.” For this reason, the RFAGC signal 113 provided to the RF AGC amplifier 602 is set to “0”, and gain of the RF AGC amplifier 602 is fixed to maximum value.

摘要翻译： 即使强制不必要的电波接近输入信号的频率，也不受不必要的电波影响的自动增益控制方式是通过延迟点电平的变化来提供的。自动增益控制系统的尺寸为 提供具有低噪声特性和高相邻扰动压迫特性的电路，当IF AGC信号112小于延迟点电平时，信号电平检测器614的输出agcerr被提供给第一环路滤波器105.由于 提供给IF AGC放大器608的IF AGC信号112是响应于IF信号的信号电平的值，输出被反馈到该放大器，并且自动执行IF增益的控制。另一方面，当输出第二环路滤波器 106是“0”时，第二比较器108的输出rfzero被设置为1，并且向第二环路滤波器106提供“0”。当第二环路滤波器106的输出不是“0”时，它被设置为 “0”，固定值-rfdump 被提供给第二环路滤波器106，并且当该环路滤波器的输出变为“0”时，第二比较器108的输出被会聚。因此，提供给RF AGC放大器602的RFAGC信号113被设置为“0 “，并且RF AGC放大器602的增益被固定为最大值。

公开(公告)号：US20080295134A1

公开(公告)日：2008-11-27

申请号：US12123798

申请日：2008-05-20

申请人： Noboru Taga ,  Takashi Seki

发明人： Noboru Taga ,  Takashi Seki

IPC分类号： G06F13/10

CPC分类号： H04N5/52 ,  H04H20/59 ,  H04H40/27 ,  H04N5/4401 ,  H04N5/46 ,  H04N21/4263 ,  H04N21/4382 ,  H04N21/6112 ,  H04N21/6143

摘要： A receiver includes: first and second tuners configured to select respectively different broadcast channels; first and second AGC control circuits configured to generate first and second AGC control signals configured to respectively control gains of first and second AGC amplifiers based on output signals of the respective tuners; first and second predetermined voltage generating circuits configured to generate first and second predetermined voltages configured to respectively suppress AGC gains of the first and second AGC amplifiers; and a control section configured to control to selectively apply the first AGC control signal and the first predetermined voltage to the first AGC amplifier, and control to selectively apply the second AGC control signal and the second predetermined voltage to the second AGC amplifier.

摘要翻译： 接收机包括：第一和第二调谐器，被配置为分别选择不同的广播信道; 第一和第二AGC控制电路，被配置为产生第一和第二AGC控制信号，其被配置为基于各个调谐器的输出信号分别控制第一和第二AGC放大器的增益; 第一和第二预定电压发生电路，被配置为产生被配置为分别抑制第一和第二AGC放大器的AGC增益的第一和第二预定电压; 以及控制部，被配置为控制以选择性地将第一AGC控制信号和第一预定电压施加到第一AGC放大器，并且控制以选择性地将第二AGC控制信号和第二预定电压施加到第二AGC放大器。

公开(公告)号：US07206279B2

公开(公告)日：2007-04-17

申请号：US10389951

申请日：2003-03-18

申请人： Noboru Taga ,  Takashi Seki

发明人： Noboru Taga ,  Takashi Seki

IPC分类号： H04J11/00

CPC分类号： H04L27/2647

摘要： An apparatus for receiving an OFDM modulated signal includes: an A/D converter converting the received signal to a digital signal; a quadrature demodulator performing quadrature detection of the digital signal and converting the digital signal to a base-band signal; an FFT circuit transforming the base-band signal to a signal of a frequency domain by performing a fast Fourier transformation; an equalizer equalizing the signal of the frequency domain and obtaining demodulated data; an error correcting circuit performing error correction and decoding the demodulated data obtained by the equalizer; an interference detector detecting a receiving quality for each predetermined frequency band from the demodulated data; and a synchronous sequencer assigning weights to the base-band signal and the signal of the frequency domain based on the receiving quality data, and reproducing a timing synchronized signal and a clock pulse required for the demodulation.

摘要翻译： 一种用于接收OFDM调制信号的装置，包括：A / D转换器，将接收信号转换成数字信号; 正交解调器，对所述数字信号进行正交检波，并将所述数字信号转换成基带信号; 通过执行快速傅里叶变换将基带信号变换为频域的信号的FFT电路; 均衡器，对频域的信号进行均衡并获得解调数据; 误差校正电路，对由所述均衡器获得的解调数据进行纠错和解码; 干扰检测器，从解调数据检测每个预定频带的接收质量; 以及基于接收质量数据向基带信号和频域的信号分配权重的同步定序器，以及再现定时同步信号和解调所需的时钟脉冲。

公开(公告)号：US5694389A

公开(公告)日：1997-12-02

申请号：US605742

申请日：1996-02-22

申请人： Takashi Seki ,  Noboru Taga ,  Shigeru Okita

发明人： Takashi Seki ,  Noboru Taga ,  Shigeru Okita

IPC分类号： H04L27/18 ,  H04J11/00 ,  H04J13/00 ,  H04J13/16 ,  H04L27/26

CPC分类号： H04L27/2657 ,  H04L27/2613 ,  H04L27/2675 ,  H04L27/2688

摘要： This invention improves the frequency acquisition range and the resistance to multipath interference. In a digital signal transmission system using OFDM, on the transmission side, some or all of a plurality of equidistant carrier positions are treated as reference carrier positions. The actual transmitted carriers are arranged in a predetermined pattern non-equidistant to the frequency carrier positions to form an OFDM symbol. This OFDM symbol is periodically transmitted as frequency reference symbols. On the reception side, the carrier arrangement pattern of the frequency reference symbols is detected, a carrier frequency offset is detected from the detected pattern offset, and the carrier frequency is compensated based on the frequency offset.

摘要翻译： 本发明改进了频率采集范围和抗多径干扰。 在使用OFDM的数字信号传输系统中，在发送侧，将多个等距的载波位置中的一些或全部视为参考载波位置。 实际发送的载波被布置成与等于载波位置的预定模式以形成OFDM符号。 周期性地将该OFDM符号作为频率参考符号发送。 在接收侧，检测频率参考符号的载波排列模式，从检测到的模式偏移检测载波频率偏移，并且基于频率偏移补偿载波频率。

公开(公告)号：US6081563A

公开(公告)日：2000-06-27

申请号：US19368

申请日：1998-02-05

申请人： Noboru Taga ,  Takashi Seki

发明人： Noboru Taga ,  Takashi Seki

IPC分类号： H04L27/227 ,  H03J7/02 ,  H04L27/00 ,  H04L27/233 ,  H04L27/06

CPC分类号： H04L27/2332 ,  H04L2027/003 ,  H04L2027/0057

摘要： A phase detection circuit detects a phase of a phase detection signal output from a complex multiplication circuit. A frequency error detection circuit detects a frequency error of a phase-detected signal, with the first frequency error detection characteristic in which a first frequency domain is defined as a detection range. An average circuit converts a signal having the detected frequency error into a signal having a second frequency error detection characteristic in which a second frequency domain other than the first frequency domain is defined as a detection range. After the average circuit calculates an average of frequency error signals for each period of time, it converts an average signal into a signal having the original first frequency error detection characteristic and outputs it to an AFC loop filter.

摘要翻译： 相位检测电路检测从复数乘法电路输出的相位检测信号的相位。 频率误差检测电路利用将第一频域定义为检测范围的第一频率误差检测特性来检测相位检测信号的频率误差。 平均电路将具有检测到的频率误差的信号转换为具有第二频率误差检测特性的信号，其中除了第一频域之外的第二频域被定义为检测范围。 在平均电路计算每个时间段的频率误差信号的平均值之后，将平均信号转换成具有原始第一频率误差检测特性的信号，并将其输出到AFC环路滤波器。

公开(公告)号：US5771224A

公开(公告)日：1998-06-23

申请号：US619211

申请日：1996-03-21

申请人： Takashi Seki ,  Noboru Taga ,  Shigeru Okita ,  Tatsuya Ishikawa

发明人： Takashi Seki ,  Noboru Taga ,  Shigeru Okita ,  Tatsuya Ishikawa

IPC分类号： H04L27/18 ,  H04J11/00 ,  H04L5/02 ,  H04L27/26 ,  H04L27/34

CPC分类号： H04L27/2657 ,  H04L27/18 ,  H04L27/2613 ,  H04L27/2675 ,  H04L27/34 ,  H04L25/0232 ,  H04L25/03159 ,  H04L27/2662 ,  H04L5/0048

摘要： A transmission system is disclosed which permits the receiving end to demodulate multi-valued modulated symbols successfully under fading conditions and reduces the amount of transmitted reference data to improve data transmission efficiency. At the transmitting end, a multiplexing section, a modulating section, and a transmitting section are provided. In transmitting an OFDM transmission frame, null symbols and reference symbols are placed in the beginning portion of the frame and QPSK symbols are placed in an information symbol data region in the frame with equal spacings in time and frequency. At the receiving end, a receiving section, a demodulation section, an equalizing section, and a demultiplexing section are provided. An error detector detects amplitude and phase errors of each carrier from the reference symbols, and a variation detector detects variations in the amplitude and phase of a received signal from the QPSK symbols. The carrier amplitude and phase errors are corrected by a correction information producing section on the amplitude and phase variations of the received signal detected by the variation detector to produce correction information. The equalizing section equalizes the demodulated symbol data according to the correction information.

摘要翻译： 公开了一种传输系统，其允许接收端在衰落条件下成功解调多值调制符号，并减少传输的参考数据量以提高数据传输效率。 在发送端，提供复用部分，调制部分和发送部分。 在发送OFDM传输帧时，将空符号和参考符号放置在帧的开始部分，并且将QPSK符号放置在帧中的时间和频率上等间隔的信息符号数据区域中。 在接收端设置有接收部分，解调部分，均衡部分和解复用部分。 误差检测器从参考符号检测每个载波的幅度和相位误差，并且变化检测器检测来自QPSK符号的接收信号的幅度和相位的变化。 载波振幅和相位误差由校正信息产生部分对由变化检测器检测到的接收信号的幅度和相位变化进行校正，以产生校正信息。 均衡部根据校正信息对解调符号数据进行均衡。

公开(公告)号：US20100202547A1

公开(公告)日：2010-08-12

申请号：US12701803

申请日：2010-02-08

申请人： Noboru Taga ,  Takashi Seki

发明人： Noboru Taga ,  Takashi Seki

IPC分类号： H04L27/28

CPC分类号： H04L27/2662 ,  H04L27/2657 ,  H04L27/2675

摘要： In an OFDM reception apparatus, a Fourier transform unit segments a time-domain signal in an OFDM signal in accordance with a segmenting window signal and converts the time-domain signal into a frequency-domain signal. A first signal extraction unit extracts pilot signals periodically arranged in a frequency direction and in a time direction from an output from the Fourier transform unit. A second signal extraction unit extracts differential reference signals from an output from the Fourier transform unit. A delay profile detection unit performs delay profile detection using the output from the second signal extraction unit, and performs delay profile detection on the output from the first signal extraction unit within a range limited on the basis of a result of the detection. A synchronous reproduction unit generates the segmenting window signal using an output from the delay profile detection unit.

摘要翻译： 在OFDM接收装置中，傅立叶变换单元根据分割窗口信号对OFDM信号中的时域信号进行分段，并将时域信号变换为频域信号。 第一信号提取单元从傅里叶变换单元的输出中提取频率方向和时间方向周期性排列的导频信号。 第二信号提取单元从傅立叶变换单元的输出中提取差分参考信号。 延迟分布检测单元使用来自第二信号提取单元的输出执行延迟分布检测，并且在基于检测结果限制的范围内对来自第一信号提取单元的输出进行延迟分布检测。 同步再现单元使用延迟分布检测单元的输出产生分割窗口信号。

公开(公告)号：US08284850B2

公开(公告)日：2012-10-09

申请号：US12701803

申请日：2010-02-08

申请人： Noboru Taga ,  Takashi Seki

发明人： Noboru Taga ,  Takashi Seki

IPC分类号： H04K1/10

CPC分类号： H04L27/2662 ,  H04L27/2657 ,  H04L27/2675

摘要： In an OFDM reception apparatus, a Fourier transform unit segments a time-domain signal in an OFDM signal in accordance with a segmenting window signal and converts the time-domain signal into a frequency-domain signal. A first signal extraction unit extracts pilot signals periodically arranged in a frequency direction and in a time direction from an output from the Fourier transform unit. A second signal extraction unit extracts differential reference signals from an output from the Fourier transform unit. A delay profile detection unit performs delay profile detection using the output from the second signal extraction unit, and performs delay profile detection on the output from the first signal extraction unit within a range limited on the basis of a result of the detection. A synchronous reproduction unit generates the segmenting window signal using an output from the delay profile detection unit.

摘要翻译： 在OFDM接收装置中，傅立叶变换单元根据分割窗口信号对OFDM信号中的时域信号进行分段，并将时域信号变换为频域信号。 第一信号提取单元从傅里叶变换单元的输出中提取频率方向和时间方向周期性排列的导频信号。 第二信号提取单元从傅立叶变换单元的输出中提取差分参考信号。 延迟分布检测单元使用来自第二信号提取单元的输出执行延迟分布检测，并且在基于检测结果限制的范围内对来自第一信号提取单元的输出进行延迟分布检测。 同步再现单元使用延迟分布检测单元的输出产生分割窗口信号。

公开(公告)号：US06983027B2

公开(公告)日：2006-01-03

申请号：US09987881

申请日：2001-11-16

申请人： Takashi Seki ,  Takeshi Koyama

发明人： Takashi Seki ,  Takeshi Koyama

IPC分类号： H03K9/00

CPC分类号： H04L27/2647 ,  H04L1/20

摘要： A demodulation circuit receives an OFDM transmit signal containing an information carrier, an additive-information transmission carrier, and a reception-synchronization pilot signal to convert these carriers and signal into frequency-axial data. The information carrier transmits information data. The additive-information transmission carrier and the reception-synchronization pilot signal have a lower multi-valued modulation degree than the information carrier. A differential detection circuit conducts detection processing by using a detection-subject symbol of a plurality of symbols indicated at a predetermined interval in the same frequency range and a symbol ahead that detection-subject symbol by a predetermined time in either one output of the additive-information transmission carrier and the reception-synchronization pilot signal output from the demodulation circuit. A first S/N ratio generating circuit generates an S/N ratio based on a detection output provided from the differential detection circuit. The S/N ratio indicates the reception quality of the OFDM transmit signal.

公开(公告)号：US07998543B2

公开(公告)日：2011-08-16

申请号：US12281008

申请日：2006-10-17

申请人： Takashi Seki ,  Takeshi Kataoka ,  Hitoshi Mazaki ,  Hirofumi Aizono

发明人： Takashi Seki ,  Takeshi Kataoka ,  Hitoshi Mazaki ,  Hirofumi Aizono

IPC分类号： C09K19/38 ,  C09K19/34 ,  C09K19/20 ,  C09K19/30 ,  C07D305/06 ,  C07D407/10 ,  C07D407/12 ,  C08G65/18

CPC分类号： C07D305/06 ,  C08F220/30 ,  C08G65/18 ,  G02F1/13363 ,  G02F2001/133633 ,  G02F2413/04 ,  G02F2413/06 ,  G02F2413/08 ,  Y10T428/10

摘要： A novel dioxetane compound is provided having a cationically polymerizable oxetane group, which compound is excellent in compatibility with a liquid crystalline compound and a non-liquid crystalline compound. An optical film is also provided with excellent liquid crystal orientation retention properties and mechanical strength, produced by aligning a composition of the dioxetane compound and a cationically polymerizable compound in a liquid crystal orientation and fixing the liquid crystal orientation by polymerization. Further, a liquid crystal display device is provided with the optical film.

摘要翻译： 提供具有阳离子聚合性氧杂环丁烷基的新型二氧杂环丁烷化合物，该化合物与液晶化合物和非液晶化合物的相容性优异。 光学膜还具有优异的液晶取向保持性和机械强度，其通过将液体取向中的二氧杂环丁烷化合物的组成和阳离子聚合性化合物取向并通过聚合固定液晶取向而制备。 此外，液晶显示装置设置有光学膜。