| abstract |
A blood flow velocity measurement device is devised where there exist such entities within the fluid which are detectable when axially flowing (passing by) an appropriate detector of known and well defined dimensions mounted onto a catheter. The entities produced for instance by a generator, when flowing by the detector, induced a known single response, the response bearing direct correlation to the flow velocity, in the form of direct reciprocity to the velocity and direct proportion to the length of the sensitive length of the detector. Autocorrelation of the function obtained by the overlap and pile-up of successive events is calculated and from the characteristic points in the autocorrelation function the axial velocity is inferred. The measurement is best when the probing beam is perpendicular to the flow. |