Fast MATLAB -based ultrasound simulation software: Time harmonic calculations

A library of fast C++ routines is created for MATLAB simulations of time harmonic pressures generated by ultrasound phased arrays. These programs are included in the recently released FOCUS software package, where FOCUS is an acronym for “fast object-oriented C++ ultrasound simulator.” FOCUS is intended for large scale phased array simulations, characterizations of beamforming strategies, and analysis of new phased array designs. This software supports nearfield simulations of individual flat circular and rectangular pistons and focused spherical shells. Routines for pressure calculations with flat and curved phased array geometries consisting of circular and rectangular elements are also included. Within the FOCUS program, time harmonic simulations are performed with a combination of the fast nearfield method and the angular spectrum approach. Comparisons of errors and computation times with competing programs are evaluated for single element and phased array calculations, and results show that, for the same peak error value, FOCUS achieves an order of magnitude or more reduction in the computation time in large phased array simulations.