基于PC机的超声多普勒频谱分析系统的研制

Development of a Doppler Ultrasound Spectrum Analysis System Based on a Personal Computer

本文介绍了一种新型的基于 PC机的血流多普勒信号频谱分析系统的研制方法。这种系统以 PC机和超声多普勒检测单元为主要硬件 ,用小波变换和短时傅里叶技术以软件形式实现了血流多普勒信号的降噪、频谱分析、最大频率曲线提取、特征点检测和声谱参数的计算。这种系统不仅成本较低 ,而且可以自动提取各种信噪比 (包括低信噪比 )条件下的血流多普勒信号的频谱特征 。

The development of a novel Doppler ultrasound spectrum analysis system based on a personal comput- er is presented in this paper.A personal computer and Doppler ultrasound detector constitute the main hardware units of the system. The signal processes,including the Doppler signal de- noising,the spectrum analysis,the maximum frequency waveform extraction,the characteristic point detection and spectrum index calculation,are implemented in software using the wavelet transform and the short- time Fourier transform (STFT) . This low- cost system can automatically extract the spectrum character of the Doppler ultrasound signals under various sig- nal- to- noise ratio (SNR) conditions,including low SNR condition,which provides more precise indices for the clinical diagnosis.