During Doppler acquisition of signal creating the spectrum belt data which displays

摘要

PROBLEM TO BE SOLVED: To obtain a method for calibrating a Doppler time/speed waveform by deciding a spread spectrum error margin with an error by the spreading of a band width, the spreading of diffraction and the spreading of an analyzing time concerning each spectral line and displaying a decided spread spectrum error. ;SOLUTION: A fast Fourier transformation means 12, a compression means 14, a gray mapping means 16, a speed tracing means 20 and a spread spectrum error margin means 22 are assembled into a digital Doppler processor. In addition, a spread spectrum error margin switch is provided for a user in a Doppler mode and at the time of turning on this switch, the spread spectrum error margin in a gray scale Doppler spectrum is colored or emphasized by some shading method. Thereby, a visible impression of a satisfactory error size is given and an optional maximum frequency within an error band colored for diagnostic index calculation is freely selected.;COPYRIGHT: (C)1999,JPO