高次多项式拟合算法在多通道采集系统中的应用

由于采集电路中的器件差异性及被测源的特定非线性导致的采样值非线性偏差,为了提高采集的精度,笔者将高次多项式拟合算法应用到多通道采集系统中.在硬件采集电路上设计了针对特定频率的滤波器及可调放大器电路,在给定特定值的情况下修正了来自于器件差异性带来的偏差,同时通过软件补偿的方法即高次多项式拟合算法解决了全量程的非线性偏差.结果表明:通道之间的最大信号偏差小于信号平均值的±1%,通过硬件及软件方面相结合的办法保证了采集系统在整个量程的高精度要求,为高精度采集系统提供了一种软件及硬件相结合的解决办法,具有一定的参考意义.

Application of High Order Polynomial Fitting Algorithm in Multi-channel Acquisition System

The sampling nonlinear deviation is caused by device difference in the acquisition circuit and specific nonlinear of measured source, in order to improve the accuracy of the acquisition, use high order polynomial fitting algorithm in multi - channel acquisition system. Design a filter for the specific frequency on the hardware acquisition circuit and adjustable amplifier circuit. The deviation caused by the difference of the device was corrected under given value condition. At the same time, through the method of software compensation, the high order polynomial fitting algorithm was used to solve the nonlinear deviation of full range. The results show that the maximum signal deviation between the channels is no more than ±1% of the signal average value, the combination of hardware and software ensured that the high precision requirements of acquisition system in the entire range. It provides a solution and reference to the high precision acquisition system, which is a combination of software and hardware.