2GSPS数字存储示波器插值算法

2GSPS digital storage oscilloscope interpolation algorithm

数字存储示波器在快时基档位工作时,由于实时采样率不够,仅能采集信号的少数样点,为了重构信号,必须进行插值。通过编程和仿真比较了三次样条插值、分段线性插值、三次插值、最邻近插值对几种不同波形的恢复结果,并计算和分析了相关的均方误差。考虑实际待测的信号的不可知性和复杂性,并权衡精度与速度,当待插信号的点数小于100点时,选用三次样条插值;当待插信号的点数不小于100点时,采用三次插值法。Matlab仿真表明,设计结果的各项性能指标均达到指定要求,设计过程简便易行。

At high sweep rates , only a few samples of the signals can be on digital storage oscillo-scope screen .To give the user a reasonable view of the signals and to measure their parameters accurate-ly, interpolation is necessary .The piecewise cubic interpolations , the piecewise linear interpolation , the piecewise nearest interpolation , the cubic spline interpolation of several different waveform of the resump-tion of results have been compared through programming and simulation and the relevant root mean squre error calculated and analyzed .To take into account the actual measured signal of the unpredictability and complexity , and weigh the accuracy and speed , the choice of the cubic spline interpolation is applied when the signal is less than 100 points , when the point of the signal into question is not less than 100 points, the piecewise cubic interpolation is applied .The design process based on Matlab is very simple and practical .