Theory of ultrasound propagation in biological medium and algorithms of its adaptive focusing at visualisation process

The paper deals with the theoretical investigation and computer simulation of the process of ultrasound broad band pulse propagation through the inhomogeneous biological medium on the basis of the solution of the wave equation for ultrasound irradiation. In ultrasound acoustical devices applicable for medicine purposes the pulse signal is used and the width of frequency band of this signal is commensurable with the carrier frequency. Besides, the biological medium in which the signal propagates, is usually characterised by strongly despersive absorption coefficient. These peculiarities cause the necessity of the accurate theroretical consideration of ultrasound pulse propagation in diagnostices imaging systems. (author)