Patent ID: 7946991

Claim:
An ultrasonic Doppler blood flow measuring device, comprising: a velocity calculating unit for calculating a blood flow velocity value of a blood within a subject biological body from a Doppler-shift detected from echo signals of ultrasonic pulses transmitted to said subject biological body; and a blood flow velocity filter means for performing filter processing of said blood flow velocity value outputted from said velocity calculating unit without being influenced by aliasing, wherein the blood flow velocity filter means comprises: a first difference calculating means for subtracting a first blood flow velocity value of a first focus point adjacent to an arbitrary focus point supplied to said blood flow velocity filter means from a blood flow velocity value of said arbitrary focus point supplied to said blood flow velocity filter means and calculating a first difference value thereof; a second difference calculating means for subtracting said blood flow velocity value of said arbitrary focus point supplied to said blood flow velocity filter means from a second blood flow velocity value of a second focus point adjacent to said arbitrary focus point supplied to said blood flow velocity filter means and calculating a second difference value thereof; a filter means for performing filter processing on said first and second difference values; and an addition processing means for adding said blood flow velocity value of said arbitrary focus point to a filter processing result from said filter means, wherein said filter means comprises: a first multiplier for multiplying said first difference value by a coefficient; a second multiplier for multiplying said second difference value by a coefficient; and an adder for adding outputted data from said first and second multipliers, and wherein said first and second difference calculating means and said adder perform a fixed decimal point calculation.