Patent ID: 7246514

Claim:
A method for locating a plurality of sensors in relation to a fixed coordinate system, the method comprising: retrieving a list of sensor pairs derived from the plurality of sensors, each sensor pair comprising a selected sensor and a neighbor sensor; for each selected sensor, determining a sensor time of flight between the selected sensor and each neighbor sensor; for each selected sensor, determining a boundary time of flight between the selected sensor and a plurality of local boundaries of the selected sensor and using the boundary time of flight to determine local exclusion regions where the selected sensor can not be located with respect to the local boundaries; for each selected sensor, calculating an updated position using the boundary time of flight between the boundaries and the sensor time of flight between each sensor pair; for each selected sensor, comparing the updated position with a previous position; and for each selected sensor, if the updated position is within a predetermined threshold of the previous position, estimating the selected sensor's location at the updated position.