Doppler sound processing method and device

Abstract

The invention discloses a Doppler sound processing method and device. The method comprises the steps of conducting Doppler imaging with a fixed pulse repetition frequency or a fixed sampling rate and acquiring orthogonal Doppler signals when a user sets a speed stage Vscale for Doppler imaging, wherein the fixed pulse repetition frequency or the fixed sampling rate is larger than a theoretical pulse repetition frequency or a theoretical sampling rate calculated according to the speed stage Vscale; conducting sound processing on the acquired orthogonal Doppler signals and playing the processed signals. Due to the fact that the pulse repetition frequency or the sampling rate is larger than the pulse repetition frequency corresponding to a flow rate gear selected by the user, sound aliasing caused by an over-low PRF is avoided during Doppler sound processing; meanwhile, when the PRF is low, due to the fact that the sound playing sampling rate is PRFmax instead of the PRF, metal sound can not occur from played signals. The Doppler sound processing method and device are easy to realize.

Description

technical field [0001] The invention relates to a Doppler sound processing technology, in particular to a method that can avoid the aliasing of the left and right channel sounds caused by spectrum aliasing, and can also eliminate the low-pitched metal that appears in the sound playback at a lower pulse repetition frequency. Acoustic Doppler sound processing method and device. Background technique [0002] As an important technology in ultrasonic diagnostic system, Doppler technology is often used in the quantitative detection of blood flow or moving tissue in the human body. When performing Doppler detection, the ultrasonic probe performs quadrature demodulation and low-pass filtering on the received human body echo signals to obtain orthogonal I and Q signals, and then performs two-way processing on the IQ signals at the same time. Spectrum calculation is performed to generate a spectrogram for display; the other channel performs noise reduction and direction separation on...

AI Technical Summary

Problems solved by technology

When the measured blood flow velocity is greater than V scale When , according to the Nyquist sampling theorem, the spectrogram will generate aliasing, and the positive and negative spectrograms may alias to opposite directions respectively. Similarly, the sound of positive and negative blood flow will also be sent to the Wrong channel, resulting in the playback of sounds mixed together, difficult to distinguish

At the same time, when the PRF is low, the playback frequency is too low due to the low sampling rate, and there is a serious metallic sound in the played sound signal

Images