Estimation of ultrasonic point echoes
نویسندگان
چکیده
One important parameter for an ultrasonic transducer is the echo it yields from a pointlike reflector. It can be measured directly but there are however certain problems connected with this. We propose an alternative method to calculate the echo from a pointlike reflector by measuring the echoes from sliding halfplanes. Using a tomographic way of reasoning, we can calculate the point echoes from these measurements. Two methods to numerically perform this inversion are dealt with. The first one is a regularization technique used in conjunction with the analytical inversion formula. The other approach was to find basis functions that are suitable for the inversion of the measurements. These basis functions depend on which norm and weight function you choose. Numerical solutions are given for chosen weight functions and the inversion is shown for both methods.
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