The results of such modeling have applications in both NDE and medical imaging. While pulsed Doppler instruments provide depth information, they utilize high peak power and exhibit aliasing problems. This new technique is based on the use of repetitive, coherent linear sweeps as the excitation signal. It has the possibility for overcoming some of the shortcomings of the pulsed Doppler method, while still giving both range and velocity information. Spectral cross-correlation of consecutive demodulated received signals is used to obtain the Doppler information.
Performance evaluation includes the modeling of behavior in realistic measurement settings.
In many materials and most biological media, acoustic waves are attenuated according to a power-law relationship. As a result, the underlying governing equations in the frequency domain cannot be directly expressed in the time domain. This project uses finite elements in conjunction with the Z-transform to study propagation and scattering phenomena in highly dispersive media. Results of this research should aid in the development of attenuation-compensated imaging algorithms. Changes in the acoustic attenuation and dispersion of pulsed acoustic waves as they propagate through the composite under cure.