Dual open and closed loop linear transmitter
    2.
    发明授权
    Dual open and closed loop linear transmitter 有权
    双开和闭环线性变送器

    公开(公告)号:US06606483B1

    公开(公告)日:2003-08-12

    申请号:US09686732

    申请日:2000-10-10

    IPC分类号: H04B104

    摘要: A linear transmitter includes an amplifier feedback loop for amplifying an input signal at a power amplifier. The feedback loop is operated in an open loop mode when the power amplifier is operating at a first operating point and is operated in a closed loop mode when the power amplifier is operating at a second operating point. The transmitter further includes an auxiliary loop coupled to the amplifier feedback loop that provides phase training for the feedback loop and power leveling when the feedback loop is operating open loop. Open loop phase training and power leveling is done during open loop transmission, without an associated training signal or training period. Stable closed loop operation can commence subsequently providing the higher power amplifier efficiency associated with the second operating point and maintaining off channel interference requirements.

    摘要翻译: 线性发射器包括用于放大功率放大器处的输入信号的放大器反馈回路。 当功率放大器在第一工作点操作时,当功率放大器在第二工作点运行时,反馈回路以开环模式工作,并且在闭环模式下工作。 发射机还包括耦合到放大器反馈回路的辅助回路,当反馈回路工作在开环状态时,该回路为反馈回路提供相位训练和功率调平。 开环相位训练和功率调平在开环传输期间完成,没有相关的训练信号或训练周期。 随后可以开始稳定的闭环操作,提供与第二工作点相关联的更高的功率放大器效率,并保持关闭信道干扰要求。

    Method and apparatus for a linear transmitter
    5.
    发明授权
    Method and apparatus for a linear transmitter 失效
    线性变送器的方法和装置

    公开(公告)号:US5564087A

    公开(公告)日:1996-10-08

    申请号:US333693

    申请日:1994-11-03

    摘要: A method and apparatus is provided for a transmitter (200) with a stable, linear response. The transmitter (200) includes an amplification stage (242), and a negative feedback correction loop (244) with a feedback signal (252). A reference signal (251) is combined with the feedback signal (252) to produce an error signal (253) for coupling to the amplification stage (242). Transmitter parameters are varied when a difference between the reference signal (251) and the error signal (253) exceeds a particular threshold.

    摘要翻译: 为具有稳定的线性响应的发射机(200)提供了一种方法和装置。 发射机(200)包括具有反馈信号(252)的放大级(242)和负反馈校正环(244)。 参考信号(251)与反馈信号(252)组合以产生用于耦合到放大级(242)的误差信号(253)。 当参考信号(251)和误差信号(253)之间的差超过特定阈值时,变送器参数是变化的。

    Method and arrangement for a sigma delta converter for bandpass signals
    6.
    发明授权
    Method and arrangement for a sigma delta converter for bandpass signals 失效
    用于带通信号的Σ-Δ转换器的方法和装置

    公开(公告)号:US4857928A

    公开(公告)日:1989-08-15

    申请号:US149350

    申请日:1988-01-28

    IPC分类号: H03M3/04 H04B14/06

    摘要: An improved apparatus and method for a sigma delta converter for bandpass signals is disclosed, suitable for use in mobile radio applications, between the front end and digital signal processing stages, that includes at least one bandpass filter, an n-level quantizer, an n-level digital-to-analog (D/A) converter, and a direct current (DC) feedback network. The sigma delta converter for bandpass signals may be configured in a second order or a fourth order embodiment and achieves analog-to-digital conversion of a signal having a non-zero frequency carrier or suppressed carrier with improved signal-to-noise ratio performance and with minimal quantization error. As a result, the sigma delta conversion occures earlier in a receiver chain and a dynamic range of about 95-98 dB is achieved.

    摘要翻译: 公开了一种用于带通信号的Σ-Δ转换器的改进的装置和方法,适用于前端和数字信号处理级之间的移动无线电应用,其包括至少一个带通滤波器,n级量化器,n 级数字模拟(D / A)转换器和直流(DC)反馈网络。 用于带通信号的Σ-Δ转换器可以被配置在二阶或四阶实施例中,并且实现具有改进的信噪比性能的具有非零频率载波或抑制载波的信号的模数转换, 具有最小的量化误差。 结果,在接收器链中发生了Σ-Δ转换,并且实现了约95-98dB的动态范围。

    Method and apparatus for control of an analog to digital converter
    10.
    发明授权
    Method and apparatus for control of an analog to digital converter 失效
    用于控制模数转换器的方法和装置

    公开(公告)号:US5389927A

    公开(公告)日:1995-02-14

    申请号:US68324

    申请日:1993-05-28

    IPC分类号: H03M1/18

    CPC分类号: H03M1/182

    摘要: An analog signal having an input level is provided. The analog signal is converted into a digitized representation of the analog signal in an analog to digital converter (105) that uses an operating range. The digitized representation of the analog signal is processed (107) to determine the input level for the analog signal. The input level for the analog signal is compared (109) with a reference signal to provide a comparison signal. The comparison signal is manipulated (111) to adjust the operating range.

    摘要翻译: 提供具有输入电平的模拟信号。 在使用操作范围的模数转换器(105)中,模拟信号被转换为模拟信号的数字化表示。 处理模拟信号的数字化表示(107)以确定模拟信号的输入电平。 将模拟信号的输入电平与参考信号进行比较(109)以提供比较信号。 操纵比较信号(111)以调整工作范围。