Method to provide a time-of-flight estimate

A TOF device to provide a time-of-flight, TOF, estimate which elapses between the emission, by an ultrasonic transducer of the TOF device, of an ultrasonic source signal and the reception, by the ultrasonic transducer of the TOF device, of an ultrasonic echo signal returned by a target body hit by the ultrasonic source signal,

• the TOF device further comprising a processing unit electrically coupled to the ultrasonic transducer and configured to:
• generate an electric echo signal indicative of the ultrasonic echo signal received;
• determine an envelope signal indicative of an envelope of the electric echo signal;
• generate a first TOF estimate by processing the electric echo signal, the first TOF estimate having a first measurement accuracy value;
• determine an envelope signal portion of the envelope signal, prior to a final time instant corresponding to a maximum value of the envelope signal, the determination of the envelope signal portion being performed using a non-PSOA hyperparameter which is selected among a plurality of non-PSOA hyperparameters as a function of the first TOF estimate;
• and
• generate a second TOF estimate by processing the envelope signal portion by means of a Particle Swarm Optimization Algorithm, PSOA, the second TOF estimate having a second measurement accuracy value greater than the first measurement accuracy value, the PSOA being optimized based on a PSOA hyperparameter set which is selected among a plurality of PSOA hyperparameter sets as a function of the first TOF estimate,
• wherein said time-of-flight estimate is the second TOF estimate.

A method, comprising:

• providing a time-of-flight, TOF, estimate, which elapses between an emission, by a TOF device, of an ultrasonic source signal and a reception, by the TOF device, of an ultrasonic echo signal returned by a target body hit by the ultrasonic source signal, by:
• generating, by the TOF device, an electric echo signal indicative of the ultrasonic echo signal received;
• determining, by the TOF device, an envelope signal indicative of an envelope of the electric echo signal;
• generating, by the TOF device, a first TOF estimate by processing the electric echo signal, the first TOF estimate having a first measurement accuracy value;
• determining, by the TOF device, an envelope signal portion of the envelope signal, prior to a final time instant corresponding to a maximum value of the envelope signal, the determination of the envelope signal portion being performed using a non-PSOA hyperparameter which is selected among a plurality of non-PSOA hyperparameters as a function of the first TOF estimate.