DESIGN OF MODULATED EXCITATION WAVEFORM BASED ON OFDM SIGNALS FOR MEDICAL ULTRASOUND IMAGING

In order to solve the conflict between resolution and penetration in medical ultrasound imaging, modulated excitation signals are adopted. The demand of higher imaging quality means that people have to design better modulated excitation waveforms. In this paper, a waveform design method based on orthogonal frequency division multiplexing (OFDM) signals is proposed for medical ultrasound imaging. A designed example is exhibited by using the proposed method. The result shows that the peak side-lobe level and the range side-lobe level of the designed signal can decrease to -80 dB and -96 dB respectively. A modified linear frequency-modulated waveform is selected as the reference waveform for evaluating the performance of the designed waveform. Simulations illustrate that the designed waveform in this paper can achieve much higher imaging quality than the reference one.