准连续调制光谱测量信号的软件锁相解调仿真与分析

Simulation and analysis of quasi continuous modulation spectral measurement signals based on software phase-locked demodulation

准连续调制光谱测量技术是准连续调制信号典型应用之一,具有灵敏度高,响应速度快、选择性好的特点,因此在炼焦工业、灾害救援、垃圾处理等领域的气体检测方面有着广泛应用。光谱测量系统中非常重要的一项内容为对输出信号进行锁相解调。传统锁相放大器进行解调难以满足准连续调制光谱高精确度测量结果的要求。因此,利用Matlab设计了软件锁相放大器,并对准连续信号解调进行仿真分析。结果表明,软件锁相放大器能够弥补传统锁相放大器的不足,在准连续调制光谱分析中可以进一步应用。

Quasi continuous modulation spectroscopy is one of the typical applications of quasi continuous modulation signals.It has the characteristics of high sensitivity, fast response and good selectivity.Therefore, it has a wide range of applications in gas detection of coking industry, disaster rescue, waste disposal and other fields.A very important part of a spectrum measurement system is the phase locked demodulation of the output signal.Demodulation using traditional lock-in amplifier is difficult to meet the requirements of high accuracy measurement results of quasi continuous modulation spectrum.Therefore, a software lock- in amplifier is designed by using Matlab, and the demodulation of the continuous signal is simulated and analyzed.The results show that the software lock-in amplifier can make up for the shortcomings of the traditional lock-in amplifier, and can be further applied in quasi continuous modulation spectrum analysis.