分裂基算法在管道腐蚀超声内检测中的应用

The application of split-radix algorithm in pipeline corrosion ultrasonic inner inspection

管道腐蚀内检测中超声回波信号具有周期性特点,功率谱估计是重要的数据处理方法之一。基于分裂基的FFT算法具有较小的乘法次数和加法次数,且算法结构较好。采用频率抽取分裂基2／4 FFT算法对管道腐蚀超声内检测回波信号进行了处理．得到管道壁厚数据,经分裂基FFT算法和基2 FFT算法比较,分裂基FFT算法明显减少了数据处理时间,提高了检测速度。理论分析和实验结果表明,该分裂基算法精度高,数据处理速度快,满足管道腐蚀内检测的实时性要求。

According to the periodic characteristic of the echo signal of the ultrasonic inner inspection on pipeline corrosion, the application of power spectrum estimation to digital ultrasonic thickness measurement has been researched. An effective method based on split radix FFT（ Fast Fourier Transform） has been put forward. A frequency abstraction split radix-2/4 FFT algorithm is introduced. Comparison of split-radix FFT with radix-2 FFT is also made. The split-radix FFT algorithm can shorten the time of program executing and enhance the speed of inspection. The test shows that the method suitable for inner inspection of pipeline corrosion.