一种四参数正弦参量估计算法的改进及实验分析

The Improvement and Experiment Analysis for a Four-Parameter Sine Wave Curve-fit Method

结合频率估计和三参数正弦波拟合实现的四参数最小二乘拟合算法,具有算法简洁、无须预估参数、无须迭代、绝对收敛、运算速度高等特点。但在实际应用中效果很不稳定,对较低位数A/D的情况,经常准确度很低或给出错误结果。针对这一问题,进行了实验分析,给出了改进措施,明确了算法使用的边界限制条件,从而为该方法的推广应用奠定了基础。数据实验结果验证了改进措施和边界条件的有效性与可行性。该改进算法可用于正弦波形4个参数的测量与估计。

To introduced a four-parameter sine wave curve-fit method, it based on the frequency estimation method, and then, combining with three-parameter sine wave curve-fit method, to realize the four-parameter sine wave curve-fit course, obtain the four parameters. The method is simple and easy to realize, it needn＇t pre-estimation of parameters and iteration, it has absolute convergent and high speed calculation course. But in case of lower A/D bites, the arithmetic method is unsteady, it always derives rough results, or wrong results. To these problems, this paper presents some experiments studies, the improvement arithmetic method is introduced, and the limitation of the method is taken out. It can be the base of the sine wave curve-fitting method in application. The correctness and rightness have proved by experiments results. The improved four-parameter sinusoidal curve-fitting method can be used in practice.