摘要
模拟接收机主要关心的问题是信号过载和外界环境对电路的影响,而数字接收机的主要问题则是A/D转换器的过载。在数字AGC中,信号经A/D转换器数字化后,增益衰减主要是通过采样数据的运算处理来完成。相对于模拟硬件电路设计的AGC而言,采用了一种用于短波数字接收机中自动增益控制(AGC)的设计方法。数字AGC具有控制平坦、建立时间快、电路结构简单和成本低等特点。在最终实现的电路性能达到了120dB的动态范围,输出信号变化小于或等于0.5dB.
The method, which is used to design AGC model applied in HF digital receiver, is presented in this paper. In analogical receiver, both the signal overload and the external interference are the primarily subjects. In digital receiver, we pay more attention to the overload of A/D converter. In our digital AGC module, analogical signal is first converted to digital signal by A/D converter, and then the control of gain is realized by the operation of sampled digital data. Compared with the analogical AGC model, the digital AGC one designed by this method, which is characteristic of flat controlled response,fast speed of setup time,low cost and simple circuit architecture, is superior to the analogical AGC model. The implemented circuit module of digital AGC has been achieved the dynamic limits of 120dB with the flatness of 0.5dB at output signal level.
出处
《桂林电子工业学院学报》
2003年第5期35-37,共3页
Journal of Guilin Institute of Electronic Technology
