FILTER CIRCUIT AND RECEIVING APPARATUS
    1.
    发明申请
    FILTER CIRCUIT AND RECEIVING APPARATUS 失效
    滤波电路和接收装置

    公开(公告)号:US20090258626A1

    公开(公告)日:2009-10-15

    申请号:US12419355

    申请日:2009-04-07

    IPC分类号: H04B1/06 H03H7/00 H04B1/16

    摘要: A filter circuit includes first capacitors, second capacitors capable of altering a cutoff frequency by being connected in parallel with the first capacitors, first switches for connecting the second capacitors in parallel with the first capacitors, and charging circuits for the second capacitors. The charging circuits include second switches, and resistances for attenuating the amplitudes of input voltages to be fed to the second capacitors, by being connected in series with the second capacitors. The second capacitors are charged through the resistances in a state where the first switches are turned OFF and where the second switches are turned ON. Thus, a DC offset which is ascribable to the cutoff frequency switching of a filter is reduced.

    摘要翻译: 滤波器电路包括第一电容器,能够通过与第一电容器并联连接来改变截止频率的第二电容器,用于将第二电容器与第一电容器并联连接的第一开关和用于第二电容器的充电电路。 充电电路包括第二开关和用于衰减要馈送到第二电容器的输入电压的振幅的电阻,通过与第二电容器串联连接。 在第一开关断开的状态和第二开关导通的状态下,通过电阻对第二电容器进行充电。 因此,降低了归因于滤波器的截止频率切换的DC偏移。

    FILTER CIRCUIT AND RECEIVER USING THE SAME
    2.
    发明申请
    FILTER CIRCUIT AND RECEIVER USING THE SAME 有权
    滤波电路和接收器

    公开(公告)号:US20110026507A1

    公开(公告)日:2011-02-03

    申请号:US12789771

    申请日:2010-05-28

    IPC分类号: H04W88/02 H03H7/01 H04B1/16

    摘要: Gain setting can be performed at high speed while reducing DC offset due to a filter cutoff frequency changeover without the need for input signal muting. A filter circuit having first and second filters is capable of allowing settings of first and second cutoff frequencies. First and second filter switch circuits and a charging circuit including a charging resistor and a charging switch are provided. For a first time period, the first switch circuit is controllably turned on while the second switch circuit is controllably turned off, thereby providing the first filter function. For a second time period, the first switch circuit is controllably turned off while the second switch circuit is controllably turned on, thereby providing the second filter function. For the first time period, the charging switch is controllably turned on so that the second capacitor is charged via the charging resistor.

    摘要翻译: 增益设置可以高速执行,同时减少由于滤波器截止频率切换引起的直流偏移,而不需要输入信号静音。 具有第一和第二滤波器的滤波器电路能够允许第一和第二截止频率的设置。 提供第一和第二滤波器开关电路以及包括充电电阻器和充电开关的充电电路。 在第一时间段中,第一开关电路被可控地导通,而第二开关电路被可控地关断,从而提供第一滤波器功能。 对于第二时间段,第一开关电路在第二开关电路被可控地接通的同时被可控制地截止,从而提供第二滤波器功能。 在第一时间段中,充电开关被可控地导通,使得第二电容器经由充电电阻器充电。

    Filter circuit and receiving apparatus
    3.
    发明授权
    Filter circuit and receiving apparatus 失效
    滤波电路和接收装置

    公开(公告)号:US08229384B2

    公开(公告)日:2012-07-24

    申请号:US12419355

    申请日:2009-04-07

    IPC分类号: H04B1/06

    摘要: A filter circuit includes first capacitors, second capacitors capable of altering a cutoff frequency by being connected in parallel with the first capacitors, first switches for connecting the second capacitors in parallel with the first capacitors, and charging circuits for the second capacitors. The charging circuits include second switches, and resistances for attenuating the amplitudes of input voltages to be fed to the second capacitors, by being connected in series with the second capacitors. The second capacitors are charged through the resistances in a state where the first switches are turned OFF and where the second switches are turned ON. Thus, a DC offset which is ascribable to the cutoff frequency switching of a filter is reduced.

    摘要翻译: 滤波器电路包括第一电容器,能够通过与第一电容器并联连接来改变截止频率的第二电容器,用于将第二电容器与第一电容器并联连接的第一开关和用于第二电容器的充电电路。 充电电路包括第二开关和用于衰减要馈送到第二电容器的输入电压的振幅的电阻,通过与第二电容器串联连接。 在第一开关断开的状态和第二开关导通的状态下,通过电阻对第二电容器进行充电。 因此,降低了归因于滤波器的截止频率切换的DC偏移。

    Filter circuit and receiver using the same
    4.
    发明授权
    Filter circuit and receiver using the same 有权
    滤波电路和接收机使用相同

    公开(公告)号:US08538364B2

    公开(公告)日:2013-09-17

    申请号:US12789771

    申请日:2010-05-28

    IPC分类号: H04B1/10 H04K3/00

    摘要: Gain setting can be performed at high speed while reducing DC offset due to a filter cutoff frequency changeover without the need for input signal muting. A filter circuit having first and second filters is capable of allowing settings of first and second cutoff frequencies. First and second filter switch circuits and a charging circuit including a charging resistor and a charging switch are provided. For a first time period, the first switch circuit is controllably turned on while the second switch circuit is controllably turned off, thereby providing the first filter function. For a second time period, the first switch circuit is controllably turned off while the second switch circuit is controllably turned on, thereby providing the second filter function. For the first time period, the charging switch is controllably turned on so that the second capacitor is charged via the charging resistor.

    摘要翻译: 增益设置可以高速执行,同时减少由于滤波器截止频率切换引起的直流偏移,而不需要输入信号静音。 具有第一和第二滤波器的滤波器电路能够允许第一和第二截止频率的设置。 提供第一和第二滤波器开关电路以及包括充电电阻器和充电开关的充电电路。 在第一时间段中,第一开关电路被可控地导通,而第二开关电路被可控地关断,从而提供第一滤波器功能。 对于第二时间段,第一开关电路在第二开关电路被可控地接通的同时被可控制地截止,从而提供第二滤波器功能。 在第一时间段中,充电开关被可控地导通,使得第二电容器经由充电电阻器充电。