Ultrasonic guided waves were widely used in aeronautics

pipeline

vessels and so on

because of its long distance propagation and large range detection property.Due to the long distance propagation along waveguides

the guided waves were not only possess the feature of ultrasonic bulk waves

but also dispersion and multi-modes characters

which limited detection effect of guided waves and increased the difficulty of feature recognition.It has great theoretical and realistic sense to research the dispersion and multi-modes for ultrasonic guided waves. In this paper

the characters of dispersion and multi-modes were analyzed carefully

and a signal processing point of view was considered.The modeling and morphology decomposition of guided waves signals were proposed by the use of morphology component analysis techniques.The validations of these methods were realized through experiments.All of research results can provide key technologies for decreasing the effect of dispersion and multi-modes and analyzing complex for guided waves signals.