基于相关法的差分式科氏流量计幅值检测算法

Correlation Theory-based Amplitude Detection Algorithm for Differential Coriolis Mass Flowmeter

为提高差分式科氏流量计幅值检测的精度,提出了基于相关法的幅值检测算法。首先构造两路与采样信号同频的参考信号,然后分别与采样信号进行互相关得到互相关信号,估计出采样信号的初相位,最后检测出采样信号的幅值。理论分析表明:该方法不受信号非整周期采样的影响。仿真实验结果表明:该方法提高了检测精度,在信噪比45d B时,测量相对误差低于0.25%。

In order to improve the accuracy of the amplitude detection for differential Coriolis Mass Flowmeter, a correlation theory-based amplitude detection algorithm is proposed. Firstly, two reference signals are generated, which are the same frequency with sampled signal. And then, cross-correlation signal is generated through cross correlation between reference signal and sampled signal, and the initial phase of the sampled signal is estimated. At last, the amplitude of the sampled signal is detected. Theoretical analysis indicates that the proposed algorithm is not affected by non-integer period of sampled signal. The simulation results indicate that the proposed algorithm improves the detection accuracy, and the relative error is less than 0. 25% when the signal to noise ratio is 45 dB.