基于LabVIEW的采样定理验证系统设计

Design of sampling theorem verification system based on LabVIEW

时域采样理论与频域采样理论是数字信号处理中的重要理论,本文首先简单介绍信号处理过程中时域采样和频域采样的原理,接着基于NI LabVIEW 2015平台,设计开发了采样定理验证系统,在时域采样系统中,对50 Hz的正弦信号,采用100 Hz和99 Hz两个信号对采样前后的波形和频谱进行分析,验证系统的可靠性,在频域采样系统中,通过对傅立叶变换之后的信号进行102点和97点采样之后的结果,来验证采样点数与原信号点数关系。通过该虚拟系统,可以很好地理解并加深对时域和频域采样定理的认识,激发学生对数字信号处理理论的兴趣。

The time domain sampling theory and frequency domain sampling theory are important in the digital signal processing. This article first briefly describes the theory of time domain sampling and frequency domain sampling in the procedure of signal processing , then based on NI LabVIEW2015 platform, the sampling theorem verification system is designed and developed. In the time domain sampling system, To the Sinusoidal signal of 50 Hz, we use the signal of 100 Hz and 99 Hz to analyze the waveform and frequency spectrum before and after sampling to verify the reliability of the system. In the frequency domain sampling system, through the result of 102 and 97 point sampling of the signal after the Fast Fourier Transform Algorithm, we can verify the relationship between the sampling points and the original signal points. Through this virtual experiment system, the student＇ s understanding of the time domain sampling theory and frequency domain sampling theory can be well deepen, which can arouses the student＇ s interest in the digital signal processing theory.