Experimental Study On Digital Design Of Doppler Ultrasound With Coded Excitation

Full digital design with coded excitation for Doppler ultrasound system is proposed to offer full-depth examination, and to improve system SNR and penetration. The experimental platform is developed based on a Doppler phantom and a transcranial Doppler system. Raw radiofrequency signals are collected from the Doppler phantom using the transcranial Doppler system, which alternately transmits non-coded and coded pulses. Software-based digital signal processing techniques are well used to reduce the scale of hardware. The results tell us that by using this design, full-depth examination and some 20dB of SNR’s improvement are achieved. Penetration ability and sensitivity become much stronger compared with traditional systems. This work will facilitate blood flow examination in clinical diagnosis.