CONTENTS
1 Introduction 3
2 Program organization 5
3 Method of simulation 7
3.1 The spatial impulse response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2 Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.3 Focusing and apodization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.4 Attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4 Installation 9
5 Description of Matlab procedures 11
5.1 List of current procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.2 Procedures for Field initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.3 Procedures for transducer definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.4 Procedures for element manipulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
5.5 Procedures for field calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
6 Examples 59
6.1 Phased array imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
6.2 Linear array imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
6.3 Flow data generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Bibliography 66
i
ii
LIST OF FIGURES
5.1 Concave, round transducer with a radius of 8 mm divided into 1 by 1 mm mathematical elements. . . 19
5.2 Rectangles for a convex array with Rconvex equal to 20 mm. . . . . . . . . . . . . . . . . . . . . . . 21
5.3 Rectangles for an elevation focused, convex array with Rfocus equal to 10 mm and Rconvex equal to
30 mm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.4 Rectangles for an elevation focused, multi-row, convex array with Rfocus equal to 7 mm and Rconvex
equal to 30 mm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.5 Rectangles for an elevation focused, linear array with Rfocus equal to 15 mm. . . . . . . . . . . . . . 26
5.6 Rectangles for an elevation focused, multi-row linear array with Rfocus equal to 10 mm and 5 rows. . 27
5.7 Display of the geometry and apodization of a linear array transducer. . . . . . . . . . . . . . . . . . . 30
5.8 Rectangles for a 16 elements linear array transducer. . . . . . . . . . . . . . . . . . . . . . . . . . . 32
5.9 Geomtery of multi-row linear array transducer. Currently x and y has been switched. . . . . . . . . . 33
5.10 Rectangles for a 16 by 5 elements multi-row transducer. . . . . . . . . . . . . . . . . . . . . . . . . . 34
5.11 Piston transducer with a radius of 8 mm divided into 1 by 1 mm mathematical elements. . . . . . . . 36
5.12 Fully populated two-dimensional array with 11 by 13 elements. . . . . . . . . . . . . . . . . . . . . . 43
5.13 Partially populated two-dimensional array with 23 elements. . . . . . . . . . . . . . . . . . . . . . . 44
5.14 Linear array transducer with a fixed apodization of the mathematical elements. . . . . . . . . . . . . 46
5.15 Intensity profile for linear array transducer with an elevation focus lens. . . . . . . . . . . . . . . . . 47
5.16 Example of calculated response when using different physical element excitations. . . . . . . . . . . 49
5.17 Received voltage traces from the individual elements of a 16 elements linear array transducer, when
transmitting with three different elements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
5.18 Received voltage traces from the individual elements of a linear array transducer (top) and the sum of
all the individual responses (bottom). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
1
2
评论0