Time domain acoustic reflectometry is proposed in this research as a method to detect atherosclerosis, estimating the location and extension of arterial obstructions by determining what is ahead of the catheter tip ("forward looking"), as opposed to the Intravascular Ultrasound (IVUS) that provides only 2D cross-sectional area images of the artery ("Side Looking") but does not provide any depth information. Since the proposed technique has not yet been investigated for liquid-filled tubes, in this research, the sound wave propagation in rigid liquid-filled tubes was studied by comparing an acoustical transmission line model predictions with measurements made in water-filled copper pipes. Model predictions underestimated energy losses and speed of sound values with errors of 40% and 120 m/s, respectively. |