在传统运用FFT进行信号插值运算的基础上,提出了一种提高插值精度的改进算法。通过子序列重叠和裁剪,舍弃重建序列边缘误差较大的样点,再将相对准确的样点进行重组,从而大幅提高插值精度。实验结果表明:与Prasad等算法相比,在计算量增加3.1%的情况下,不同子序列长度对应的归一化均方误差平均下降至原来的1/19;在计算量增加2倍的情况下,不同子序列长度对应的归一化均方误差平均下降至原来的1/75。
On the basis of the traditional interpolation algorithm using FFT, an algorithm is proposed to improve the accuracy of interpolation. The algorithm overlaps and cuts the subse-quences. Then it discards the samples with great error at both ends of interpolated sequence and reconstructs the relatively accurate samples. In this way, the accuracy of interpolation can be significantly improved. Experimental results show that, compared with the interpolation al- gorithm proposed by Prasad, in case of computational amount increasing by 3.1% the nor- malized mean square errors corresponding to different subsequence lengths decrease to 1/19 of their original in average. In case of computational amount increasing hy twice, the normalized mean square errors corresponding to different subsequence lengths decrease to 1/75 of their original in average.