Pulse Compression for Finite Amplitude Distortion Based Harmonic Imaging Using Coded Waveforms

Abstract

Finite amplitude distortion based harmonic imaging has been used to reduce the image quality degradation produced by tissue inhomogeneities. Such harmonic signals are significantly lower than the linear components and are possibly too low compared to the dynamic range of the imaging system. To improve signal-to-noise ratio (SNR) without exceeding regulatory limits, coded excitation is explored. In addition, pulse compression schemes suitable for finite amplitude distortion based harmonic imaging are also developed. Note that due to the differences in harmonic generation, these compression schemes are different from those proposed for harmonic imaging using contrast agents. In this paper, simulation examples of SNR improvements by up to 8.2dB are shown and the efficacy of the compression schemes is studied. Potential sources of performance degradation are also discussed.