Abstract
An effective method for analyzing quantitatively mode distribution of laser-generated Lamb waveforms in a fiber reinforced composite plate is presented by using the Wigner distribution (WD). The carrying energy of each mode in the waveforms is calculated quantitatively by employing time-frequency filtering technique of the WD. We found that energy conversions among modes have happened in the process of propagation of Lamb waves. These energy conversions are attributed to microstructure scattering of ultrasonic wave by the fibers in fiber reinforced composite material. (Author)