Detection of scatters motion induced by mechanical vibrator using 7-chip barker-coded excitation

Most of the ultrasound elasticity imaging techniques can´t improve the resolution and penetration at the same time. Coded excitation has displayed the capability to improve the penetration by transmitting coded waves and decoding the RF echoes. But the effectiveness of this technique in ultrasound elastographic imaging methods has not been fully demonstrated. This paper introduces a phase modulation coded Doppler detection system for detecting submicron harmonic motion induced by mechanical vibrator. It incorporates an arbitrary waveform generator which produces desired excitation waveform, low-frequency signal for mechanical vibrator, RF trigger-acquisition signal and clock signal. The vitro pork and the Model 049 Elasticity QA Phantom experiments show that 7-chip Barker code excitation Doppler technique can acquire up to 15 dB signal-to-noise ratio improvement and the detection depth is increased greatly in contrast to traditional pulse echo ultrasound technique.