Accurate characterization of ultrasonic guided waves propagating in cortical bone acquired by a single transmitter-receiver pair using adaptive signal processing

摘要: The characterization of Lamb waves propagating in cortical bone is important for diagnosing quality. Using fewer transmitters and receivers desirable low-cost diagnosis. Thus, this study, we propose a method based on an adaptive beamforming technique to characterize using single transmitter-receiver pair. We begin by estimating the longitudinal shear wave velocities as these are primary determinants transfer function. frequency domain interferometry (FDI) with Capon method, which one signal processing methods, accurately estimates position having same components reference wave. high-frequency zeroth-order modes almost non-dispersive. Therefore, use transmitted apply where phase velocity converge Rayleigh velocity. Because determined velocities, can estimate candidates estimated Finally, calculate function least squares (LSM) applied velocities. conduct 2-D numerical simulations semi-analytical finite element method. center 1.0 MHz, thickness 5.0 mm, signal-to-noise ratio 20 dB, 4430 2120 m/s, respectively, distance from transmitter receiver 21 mm. eight fitting process LSM. predicted were 4458 2116 residue normalized respect received intensity was −16 dB. proposed predicts waveforms