Comparison of Apodized Linear FM Chirp and Complementary Series Phase Encoding for Diagnostic Ultrasound Imaging by Reduced Peak Power Transmission Waveform

Abstract

A cosine-square apodized linear FM chirp signal is proposed for a spread energy transmission wave form to be used in diagnostic ultrasound imaging with reduced peak power for insonification to improve patient safety. Comparison is made with complementary series phase encoding in terms of time sidelobe levels. Results indicate that apodized chirp waveform could have a time sidelobe of less than -60 dB under practical conditions, while being relatively robust against media dispersion. Since this waVe form can converge on each time by itself without aid of another sequence, inter-sequence Doppler shift is almost no problem for the time sidelobe.