A method of measuring the speed of a fluid comprising the following steps:



generating a plurality of pseudorandom frequencies (fus_n);
for each pseudorandom frequency (fus_n), emitting ultrasound signals into the fluid to travel along a path of defined length;
receiving the ultrasound signals;
for each received ultrasound signal, producing a travel time measurement, so as to generate for each pseudorandom frequency (fus_n) a predefined number of travel time measurements;
for each pseudorandom frequency (fus_n), evaluating the accuracy of the measurements;
for evaluating the speed of the fluid, making use of the measurements produced for the pseudorandom frequency that presents the greatest accuracy.