针对以快速傅里叶变换为代表的常用二阶统计量在处理输油管道腐蚀超声回波 信号时经常出现大量误差的问题，详细研究了管道超声回波信号的形成原理，并运用波动 理论对回波信号进行特征分析，提出了基于 1. 5 维谱估计的非最小相位系统与非高斯信 号处理方法，并对管壁正常位置、出现内壁腐蚀和外壁腐蚀位置分别进行了逐点扫描检测 及超声回波信号分析，同时给出了一种特殊的管壁腐蚀临界位置回波信号处理方法． 单点 检测和多点连续检测实验结果表明，1. 5 维谱估计算法分析输油管道腐蚀超声回波信号 时，能够有效克服快速傅里叶变换算法的弊端，获取的壁厚相对误差在 2% 以内，C 扫描 图像能够清晰地显示管道的腐蚀情况，满足输油管道腐蚀剩余壁厚的检测要求．

The frequently used second-order statistics represented by fast Fourier transform often cause many errors in processing the ultrasonic echo signals of pipeline corrosion． To solve the problem，the formation principle of the pipeline ultrasonic echo signal was studied，and the characteristics of the echo signal were analyzed with the wave theory． A processing method of non-minimum phase system and non-Gaussian signal based on 1. 5-D spectrum esti- mation was proposed． Scanning detection and ultrasonic echo signal analysis were carried out for the normal location of pipe wall，the location of inner wall corrosion and outer wall corrosion respectively． And a special method of echo signal processing for the critical location of corrosion on pipe wall was given． Experimental results of single-point detection and multi-point continuous detection show that 1. 5-D spectrum estimation algorithm can effectively over- come the shortcomings of fast Fourier transform algorithm when analyzing the ultrasonic echo signal of the oil pipe- line corrosion． The relative error of wall thickness obtained is less than 2%． C-scan image can clearly show pipe- line corrosion，which meets the detection requirements of the residual wall thickness of the oil pipeline corrosion．