Patent ID: 8622909
Filing Date: 2014-01-07
Classification: A61B,G01S

Abstract:
1. A method of detecting a target in a medium, comprising: a) generating an ultrasound signal having a modulation envelope and causing the ultrasound signal to impact the target; b) demodulating the ultrasound signal having a modulation envelope through the interaction of the ultrasound signal having a modulation envelope and the target and receiving the demodulated signal by at least one sensor to determine that a detected target is present in the medium; c) determining a location of a detected target in one dimension from a distance of at least one sensor to the target in the medium by measuring the time-of-flight of the demodulated signal to the at least one sensor having a known location, the distance between the at least one sensor and the target being calculated by multiplying the time-of-flight by the sound speed in the medium; d) the at least one sensor yields at least one distance value from the signal emitting target; e) the modulated ultrasound signal is confined substantially to linear beam; f) an error function is defined for each sensor for each point along a line coincident to the modulated ultrasound beam; g) the error function is based on a difference between the distance determined by the sensor and the actual distance to each point along the line; h) a cost function is defined for each point along the line based upon a combination of the error functions for each sensor, the minimization of which estimates the position along the line of the source of radiation (i.e. the signal emitting target); and i) the cost function is based upon a weighted sum of the error functions for each sensor.