一种可变带宽模拟信号预处理电路设计

介绍了一种数控可变带宽弱信号高放大量多路模拟信号预处理机的电路原理,分析了该系统设计的基本要求,并描述了由SHARC ADSP-21160 DSP控制的自动增益控制电路(AGC)和可变带宽的带通滤波器电路原理,该系统既可以用于宽带,也可以用于窄带系统,为实现灵活多样的数字信号处理算法提供了条件。介绍了该系统在研制过程中解决的电源抗干扰设计、地线设计和屏蔽等保证系统可靠工作的几项措施,并给出了测试结果,实验证明该系统是切实可行的,其成果已应用于水声信号处理工程项目中。

Design of a Preprocessor Circuit for Variable Bandwidth Analog Signals

The principle of preprocessor circuit for amplifying highly multiplex weak analog signals with digital controlled variable bandwidth is introduced,and the basic requirement for designing the preprocessor is presented.The principles of automatic gain control(AGC) circuit and bandpass filters circuit with variable bandwidth,which are controlled by the digital signal processor(DSP) of SHARC ADSP-21160,are analyzed.The preprocessor can be applied to the narrow-band and the wide-band system,and facilitates the design of flexible DSP algorithms.The problems of the power anti-interference,ground wire and shield are solved in the design process to guarantee the system reliability,and the test results are given.The experimantal result and engneering application show that the preprocessor is practicable.