Investigating ultraharmonic modeling from ultrasound echo signal with SISO volterra filter

In general, a single-input-single-output (SISO) Volterra series cannot be used for modeling component of ultraharmonic frequency from ultrasound echo signal. In this paper we present a new method for modeling the ultraharmonic component based on a SISO Volterra filter with exciting input signal at half-fundamental frequency. Results from the approach of the SISO Volterra show capability for successful modeling of the ultraharmonic. We have investigated the accuracy of predicting the ultrasound echo signal under different noise levels. In addition, the SISO Volterra can be still modeled subharmonic frequency component. This is significant solution for separating the ultraharmonic only or adding both the sub- and ultraharmonic for contrast imaging by the system identification of the SISO Volterra filter.