| Guided waves have been observed to travel long distance through thickness in long bones and potentially provide valuable information about bone properties and microstructures. In this work, cylindrical ultrasound guided waves in bovine tibia using axial transmission technique were investigated. Numerical simulation and phantom data were used to verify the analytic procedures and complement the study. The 2-D power spectrum of the bone data was estimated using the periodogram. The spectral results showed four distinct energy clusters. Theoretical dispersion curves based on a viscoelastic cylindrical tube filled with liquid were computed to assist the modal identification. Four high-order longitudinal cylindrical guided wave modes were identified to associate with the clusters. The time signatures of the two strongest modes demonstrated dispersive wave trains, which were in agreement with the theoretical results. This study demonstrated that cylindrical longitudinal guided waves were dominant in bovine tibia at large distance from the transmitter. |
