Coded Tissue Superharmonic Imaging: An Analytical Study

Superharmonic imaging (SHI) benefits medical ultrasound imaging in achieving higher spatial and contrast resolution but gives poor signal-to-noise ratio (SNR) and penetration depth that require careful control on excitation power and frequency. In the present work, coded pulsed excitations (linear frequency modulated and nonlinear frequency modulated signals) are used to evaluate the superharmonic field generation and propagation (coded tissue superharmonic imaging). The evaluation includes the study of parameters such as peak side lobe level, beam width, axial level for analyzing SNR and penetration depth. The results for coded tissue SHI are reported in comparison with conventional SHI and with the performance of coded tissue harmonic imaging and fundamental ultrasound imaging.