An Adaptive Pulse Compression Filter for Ultrasound Contrast Harmonic Imaging

Jenho Tsao, Ming-Huang Chen

Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University.
Ultrasound Contrast Imaging; Square Law Pulse Compression; Adaptive Pulse Compression.

DOI: 10.4236/eng.2013.510B024                

Abstract

Coded excitation is useful for ultrasound contrast imaging to increase penetration and SNR, and improve the contrast to tissue ratio (CTR). The waveform of bubble response depends greatly on bubble size, the frequency and bandwidth of the excitation chirp signal. This makes the pulse compression filter based on square-law be wrong for bubbles with changing sizes. In this paper, an adaptive pulse compression (APC) filter for the second harmonic of microbubble with varying size distribution is proposed. The APC filter is designed based on the estimated power spectrum of the received bubble harmonic echoes. Theoretical analysis and simulation studies are presented for evaluating performance of the APC filter. For monodisperse bubble, the power improvement factor of the APC filter can be more than 20 dB.

Keywords

Ultrasound Contrast Imaging; Square Law Pulse Compression; Adaptive Pulse Compression

Conflicts of Interest

The authors declare no conflicts of interest.

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