Ascertaining spectral width of Doppler signals - measuring ratio of auto-correlation functions at null and pulse period displacement positions

摘要

A method of measuring Doppler signal spectral width involves transmitting pulses of defined frequency into a region with moving particles, dividing the reflected echo signals into quadrature components, forming autocorrelation functions at null and pulse time displacement positions and determining the spectral width from their ratio. The cross-correlation component (Kiq (Tr)) at the pulse repetition time position is formed from the in-phase (i) and quadrature (q) components and the quotient multiplied by a correction factor before determining the spectral width. USE/ADVANTAGE - Esp. for measuring blood flows in medical diagnostics. Accurate measurement of Doppler spectrum variance and turbulence is achieved.