Abstract: According to the measurement,control and signal processing requirements of chemical machinery and equipment,and taking two PCs connected with Ethernet as hardware platform,a multi-function virtual signal spectrum analyzer was developed using virtual instrument graphical development software package LabVIEW as software development tool.The arbitrary signal generator virtual instrument (VI) module was developed on a PC,and the spectrum analyzer VI module was designed on the other.The arbitrary signal generator VI module could generate two channels waveform signal with additive white noise.On the other hand,the spectrum analyzer VI module collected the waveform signal adding with noise generated by the arbitrary signal generator VI module through Ethernet,and carried out low pass filtering,window smoothing processing,amplitude spectrum and phase spectrum analyzing to the waveform signal.The test results on chemical machinery monitoring of a pilot plant showed that the virtual signal spectrum analyzer had good performance.

Key words: virtual instrument, signal generator, digital filtering, window function, spectrum analysis

摘要： 根据化工机械设备的测控和信号处理要求，用以太网通讯对接的两台PC机为硬件平台，以虚拟仪器图形化开发软件LabVIEW为开发平台，设计了一套多功能信号频谱分析仪。在1台PC机上开发了任意信号发生器虚拟仪器（virtual instrument，VI）模块，在另1台PC机上开发了频谱分析仪VI模块。任意信号发生器VI模块生成2路可叠加白噪声的波形信号。频谱分析仪VI模块通过以太网采集任意信号发生器VI模块输出的带噪声的波形信号，对其进行低通滤波、加窗平滑处理，完成波形信号的幅值谱和相位谱分析。在某化工试验车间的化工设备运行稳定性监测应用试验结果表明，该频谱分析仪的各项性能良好。

关键词: 虚拟仪器, 信号发生, 数字滤波, 窗函数, 频谱分析