Automatic gain control apparatus
    1.
    发明授权
    Automatic gain control apparatus 失效
    自动增益控制装置

    公开(公告)号:US06934522B2

    公开(公告)日:2005-08-23

    申请号:US09886377

    申请日:2001-06-22

    CPC分类号: H03G1/04 H04B1/28

    摘要: In an automatic gain control amplifier, an RF automatic gain controller controls the gain of a radio frequency signal. A frequency converter frequency-converts the radio frequency signal into an intermediate frequency signal. An IF automatic gain controller controls the gain of the intermediate frequency. A level detector detects a signal level of the gain-controlled intermediate frequency signal, and generates a level signal. An automatic gain control signal generator separately controls, based the level signal, the RF automatic gain controller and the IF automatic gain controller.

    摘要翻译: 在自动增益控制放大器中,RF自动增益控制器控制射频信号的增益。 变频器将射频信号频率转换成中频信号。 中频自动增益控制器控制中频增益。 电平检测器检测增益控制中频信号的信号电平,并产生电平信号。 自动增益控制信号发生器基于电平信号单独控制RF自动增益控制器和IF自动增益控制器。

    Automatic gain control for digital demodulation apparatus
    2.
    发明授权
    Automatic gain control for digital demodulation apparatus 失效
    数字解调装置的自动增益控制

    公开(公告)号:US07054395B2

    公开(公告)日:2006-05-30

    申请号:US09853682

    申请日:2001-05-14

    IPC分类号: H04L27/08

    CPC分类号: H03G3/3089

    摘要: A digital demodulation apparatus automatically controls gain based on a state of receiving a digital modulated signal. The digital demodulation apparatus amplifies a digital modulated signal wave received through the air with the gain automatically controlled so as to have a predetermined amplitude. In the digital demodulation apparatus, a receive level variation detector detects receive level variation, an amount of noise components of the received digital signal wave. A gain controller 15 controls the gain with a receive level variation adaptive control signal based on the detected receive level variation, the amount of noise components.

    摘要翻译: 数字解调装置根据接收数字调制信号的状态自动控制增益。 数字解调装置以自动控制的增益放大通过空气接收的数字调制信号波,以具有预定的幅度。 在数字解调装置中,接收电平变化检测器检测接收电平变化,接收的数字信号波的噪声分量的量。 增益控制器15基于检测到的接收电平变化,噪声分量的量,利用接收电平变化自适应控制信号来控制增益。

    Synchronization detection apparatus
    3.
    发明授权
    Synchronization detection apparatus 失效
    同步检测装置

    公开(公告)号:US07133481B2

    公开(公告)日:2006-11-07

    申请号:US10311638

    申请日:2002-04-05

    IPC分类号: H04L7/00

    摘要: An input signal DT contains a segment synchronization signal compliant with the ATSC standard. A clock multiplication section 111 multiplies a clock CK. A switchable sampling section 112 selects a sample point from among a plurality of timing points that are defined by the multiplied clock, and samples the input signal DT at the selected sample point. Moreover, the switchable sampling section 112 switches sample points from one to another in a synchronization-unestablished state. Once the segment synchronization is established, a synchronization detection device may maintain a synchronization-established state until the field synchronization detection fails, or the synchronization detection device may output a synchronization detection signal after shifting it in the time direction based on a bit error rate RT of the input signal.

    摘要翻译: 输入信号DT包含符合ATSC标准的片段同步信号。 时钟倍增部分111将时钟CK相乘。 可切换取样部112从由倍增时钟定义的多个定时点中选择采样点,并对选择的采样点对输入信号DT进行采样。 此外,可切换采样部112在同步未建立状态下将采样点从一个切换到另一个。 一旦段同步建立,同步检测装置可以保持同步建立状态,直到现场同步检测失败,或者同步检测装置可以在基于位错误率RT在时间方向上移动同步检测信号之后输出同步检测信号 的输入信号。

    Digital broadcast receiving apparatus
    4.
    发明授权
    Digital broadcast receiving apparatus 失效
    数字广播接收装置

    公开(公告)号:US07302021B2

    公开(公告)日:2007-11-27

    申请号:US09878427

    申请日:2001-06-12

    IPC分类号: H04L27/08

    摘要: In a digital broadcast receiving apparatus for amplifying a received modulated digital signal wave with automatically adjusted gain and demodulating the modulated signal wave to a digital signal, a tuner frequency-converts the modulated digital signal wave to generate a first modulated signal. A first automatic gain control amplification unit controls gain of the tuner to make a level of the first modulated signal at a first predetermined level. An A/D converter converts the first modulated signal into a second modulated signal. A demodulator demodulates the second modulated signal to generate a first demodulated digital signal. A second automatic gain control amplifier generates a second demodulated digital signal where frequency fluctuations included in the digital modulated wave are eliminated.

    摘要翻译: 在一种数字广播接收装置中,用于利用自动调节增益放大接收到的调制数字信号波并将调制信号波解调为数字信号,调谐器对调制数字信号波进行频率转换以产生第一调制信号。 第一自动增益控制放大单元控制调谐器的增益使第一调制信号的电平达到第一预定电平。 A / D转换器将第一调制信号转换成第二调制信号。 解调器解调第二调制信号以产生第一解调数字信号。 第二自动增益控制放大器产生第二解调数字信号,其中消除了数字调制波中包括的频率波动。

    Digital demodulation device and synchronization detecting method
    5.
    发明授权
    Digital demodulation device and synchronization detecting method 有权
    数字解调装置和同步检测方法

    公开(公告)号:US07333576B2

    公开(公告)日:2008-02-19

    申请号:US10342218

    申请日:2003-01-15

    摘要: A synchronization error occurs when a DTV signal is distorted on a transmission path and this deteriorates demodulation capability. The digital demodulation device and the synchronization detecting method of the invention can correct the synchronization position when determining that a synchronization error has occurred. A controller receives a center tap coefficient, for example, from a waveform equalizer and compares the coefficient with a given center tap coefficient threshold. If the coefficient is smaller than the threshold, the controller determines that a synchronization detector has made a synchronization error and outputs a control signal. The synchronization detector receiving the control signal re-detects a sync signal included in a received signal, to detect a new correct sync signal and thus correct the synchronization error.

    摘要翻译: 当DTV信号在传输路径上失真时,发生同步错误,并且这会降低解调能力。 本发明的数字解调装置和同步检测方法可以在确定发生同步错误时校正同步位置。 控制器例如从波形均衡器接收中心抽头系数,并将系数与给定中心抽头系数阈值进行比较。 如果系数小于阈值,则控制器确定同步检测器已经做出同步误差并输出控制信号。 接收控制信号的同步检测器重新检测包含在接收信号中的同步信号,以检测新的正确同步信号,从而校正同步误差。

    VSB receiver
    6.
    发明授权
    VSB receiver 有权
    VSB接收机

    公开(公告)号:US06671002B1

    公开(公告)日:2003-12-30

    申请号:US09555150

    申请日:2000-08-07

    IPC分类号: H04N544

    摘要: The loop gain of an AGC circuit 7 and the loop gain of a clock regenerating circuit 6 are increased (the gain of an amplifier is increased, or the band of a loop filter is widened) until a synchronizing signal (a segment synchronizing signal or a field synchronizing signal) is detected. The loop gain of the AGC circuit 7 and the loop gain of the clock regenerating circuit 6 are decreased (the gain of the amplifier is decreased, or the band of the loop filter is narrowed) after the synchronizing signal is detected. Consequently, it is possible to make a reduction of a time period required until convergence processing is completed in the AGC circuit and the clock regenerating circuit compatible with an improvement of a ghost disturbance removal performance and accurate clock regeneration.

    摘要翻译: AGC电路7的环路增益和时钟再生电路6的环路增益增加(放大器的增益增加或环路滤波器的频带被加宽),直到同步信号(段同步信号或 场同步信号)。 在检测到同步信号之后,AGC电路7的环路增益和时钟再生电路6的环路增益被减小(放大器的增益减小或环路滤波器的频带变窄)。因此, 可以减少在AGC电路和时钟再生电路中的会聚处理完成所需的时间段,其与改善重影干扰去除性能和精确的时钟再生相兼容。

    Digital broadcast receiver
    8.
    发明授权
    Digital broadcast receiver 失效
    数字广播接收机

    公开(公告)号:US6075829A

    公开(公告)日:2000-06-13

    申请号:US865829

    申请日:1997-05-30

    IPC分类号: H04H40/18 H04L27/06

    摘要: A digital broadcast receiver for receiving a digital modulation signal of the present invention includes channel selection means inputting a digital modulation signal of a radio frequency band and frequency converting a desired digital modulation signal into a designated intermediate frequency signal; oscillation means for generating a local oscillation signal used for frequency conversion at the channel selection means; oscillation frequency control means for controlling a frequency of the local oscillation signal at the oscillation means; phase noise characteristic control means for improving a phase noise characteristic of the local oscillation signal generated at the oscillation means; filter means for extracting the intermediate frequency signal selected at channel selection means; orthogonal detection means for orthogonally detecting the intermediate frequency signal extracted at the filter means; A/D converter means for converting the analog output of the orthogonal detection means into a digital signal; and digital demodulation means for digitally demodulating the output of the A/D converter means; and makes a high performance digital reception possible which can improve an AFC function by the channel selection means and can improve a bit error rate at the same time.

    摘要翻译: 用于接收本发明的数字调制信号的数字广播接收机包括:信道选择装置,输入无线电频带的数字调制信号,并将期望的数字调制信号频率转换成指定的中频信号; 用于在频道选择装置处产生用于频率转换的本地振荡信号的振荡装置; 振荡频率控制装置,用于控制振荡装置处的本地振荡信号的频率; 相位噪声特性控制装置,用于改善在振荡装置产生的本地振荡信号的相位噪声特性; 滤波器装置,用于提取在频道选择装置处选择的中频信号; 正交检测装置,用于正交检测在滤波装置处提取的中频信号; A / D转换装置,用于将正交检测装置的模拟输出转换成数字信号; 以及数字解调装置,用于数字解调A / D转换装置的输出; 并且可以实现高性能数字接收,这可以通过信道选择装置改善AFC功能,并且可以同时提高误码率。

    Receiving apparatus
    9.
    发明授权
    Receiving apparatus 失效
    接收装置

    公开(公告)号:US6072999A

    公开(公告)日:2000-06-06

    申请号:US829978

    申请日:1997-04-01

    CPC分类号: H01P1/20336

    摘要: A receiving apparatus is presented, in which a channel frequency can be selected over a wide band with an increased attenuation at an image frequency and/or at a local oscillation frequency by including a tunable filter having a following construction. Microstrip lines are connected between either one of the input or the output terminal or both of the input and output terminals of the tunable filter; a plurality of resonant circuits are formed by each of a plurality of coils and a plurality of variable capacitance diodes; and the coils are electromagnetically coupled and where a voltage applied to each cathode of each of a plurality of variable capacitance diodes through each of a plurality of resistors is controlled to tune a frequency to be received.

    摘要翻译: 提出了一种接收装置,其中可以通过包括具有以下结构的可调谐滤波器在宽频带上选择具有在图像频率和/或本地振荡频率处的增加的衰减的信道频率。 微带线连接在可调谐滤波器的输入或输出端子之一或输入和输出端子之间; 由多个线圈和多个可变电容二极管中的每一个形成多个谐振电路; 并且线圈被电磁耦合,并且其中通过多个电阻器中的每一个施加到多个可变电容二极管中的每一个的每个阴极的电压被控制以调谐待接收的频率。

    Synchronizing signal detecting device
    10.
    发明授权
    Synchronizing signal detecting device 有权
    同步信号检测装置

    公开(公告)号:US6069667A

    公开(公告)日:2000-05-30

    申请号:US171079

    申请日:1998-10-13

    CPC分类号: H04N5/08

    摘要: In a Sync signal detection circuit for detecting a Sync signal included in a television signal transmitted in a digital mode, pattern check means 2 checks a pattern of a Sync signal which is super imposed on a series of input data with a reference pattern. Based on a check result, Sync detection determination means 5 outputs a Sync detected signal or a Sync non-detected signal. Sync detection initialization means is further provided to this detection circuit for outputting forcibly a Sync non-detected signal when a signal of a series of input data is switched over. As a result, a Sync signal can be detected within a shorter period than the conventional circuit structure.

    摘要翻译: PCT No.PCT / JP98 / 00538 Sec。 371日期:1998年10月13日 102(e)1998年10月13日PCT PCT 1998年2月10日PCT公布。 第WO98 / 36558号公报 日期1998年8月20日在同步信号检测电路中,检测包含在以数字模式发送的电视信号中的同步信号,模式检查装置2检查超级施加在一系列输入数据上的同步信号的模式, 参考模式。 基于检查结果,同步检测确定装置5输出同步检测信号或同步未检测信号。 当一系列输入数据的信号被切换时,同步检测初始化装置还被提供给该检测电路,用于强制输出同步未检测信号。 结果,可以在比传统电路结构更短的周期内检测同步信号。