基于参数估计法的互相关流量测量系统

Cross-correlation Flow Measurement System Based on Parameter Estimation Method

摘要:

为了提高直接利用互相关函数的极大值求取渡越时间τ₀的精度,故采用参数估计法求取流动噪声的脉冲响应函数即参数模型的尖峰位置,该算法是对参数模型中的h不断地修正,算法收敛时得到τ₀；该系统主控器采用多核处理器OMAP3530,将随机信号采集、人机交互、通信接口驱动等任务在 ARM 上运行,而参数估计法的任务由DSP来承担,提高系统的实时性；实验数据表明,参数估计算法的测量误差均在1%左右,可以有效地提高测量精度,具有一定的工程应用前景。

Abstract:

In order to improve accuracy of the time-of-flight using cross-correlation function maximum, parameter estimation method is used to calculate peak position of model impulse response function which is the flow noise parameter model. Parameter h in the model is constantly revised in this algorithm. The numerical τ₀ is obtained when the algorithm is convergent. The multi-core processors OMAP3530 is the main controller for the system. The tasks of the random signal acquisition, man-machine interface and communication interface driving are accomplished in ARM. The parameter estimation method program is achieved by DSP. Thus real-time performance of the system is improved. The experimental data show that, it has high precision by using the parameter estimation method to obtain τ₀. It has certain engineering application prospects.