用PC声卡采集超低频信号的方法  

A Method of Acquiring Ultralow Frequency Signals Using PC Sound Card

作　　者：牛立全[1] 

机构地区：[1]天津公安警官职业学院 天津 300382

出　　处：《微计算机应用》2004年第1期64-69,共6页Microcomputer Applications

摘　　要：本文介绍了在把超低频信号输入PC声卡之前,在PC外部对超低频信号的处理方法、软件实现已调信号的解调和滤波的原理和方法,并给出了实现数字滤波器的部分C语言源程序。该方法具有成本低、多通道工作实时性好的特点,具有实用价值。In this paper, the method of processing Ultralow Frequency Signals outside PC before the signals being inputted PC, and the theories and methods to demodulate and filter the signals, which have being modulated on audio frequency carriers, using software are given. The aim is to acquire and display on screen Ultralow Frequency Signals. The method is that the Ultralow Frequency Signals to be acquired are regulated outside PC and modulated on audio frequency carrier signals in linear amplitude modulating; and then, by the means of programming, the modulated signals are acquired using PC sound card and demodulated and filtered. So the original Ultralow Frequency Signals have being restored and displayed on screen. The conclusion is that the method has the characteristics of low cost, multi - channel working well and is worth of using in practice.

关 键 词：PC声卡 超低频信号 采样频率 数据格式 A/D转换器 计算机 

分 类 号：TP274.2[自动化与计算机技术—检测技术与自动化装置]