Patent ID: 8010314

Claim:
A method of estimating information about the location of a tangible object or phenomenon, the method comprising, with a computer, automatically: (a) receiving input data defining the measured sum or difference of (1) a travel time of a signal along a first leg, extending between an object or phenomenon and equipment at a first transmitting or receiving location, and (2) a travel time of a signal along a second leg, extending between the object or phenomenon and equipment at a second transmitting or receiving location, different from the first transmitting or receiving location; (b) calculating, using a function, output data defining at least one location for which the sum or difference of travel time along the first leg and second leg would match, at least subject to measurement error and precision, the input data defining the measured sum or difference of travel time, even if average signal speed along the first leg differs from corresponding average signal speed along the second leg and wherein the function: (i) relates (A) relative or absolute locations of the equipment at the first and second transmitting or receiving locations, (B) signal speed along the first leg and signal speed along the second leg, (C) sum or difference of travel time, and (D) location of the object or phenomenon; (ii) defines a non-linear relationship between (A) relative or absolute locations of the equipment at the first and second transmitting or receiving locations, and (B) location of the object or phenomenon; and (iii) defines a non-linear relationship between (A) signal speed along the first leg and signal speed along the second leg, and (B) location of the object or phenomenon; and (c) storing or displaying the output data, calculated using the function.