Patent ID: 8626451

Claim:
A method for representing in a sensor processor controller the response characteristics of a first reference gas sensor to a plurality of gas species, the method comprising the steps of a) measuring the output of the first reference gas sensor while exposing the first reference gas sensor to a gas mixture comprising a predetermined concentration of a first gas species in the presence of a fixed concentration of a second gas species; b) repeating step a) for a number of different concentrations of the first gas species; c) measuring the output of the first reference gas sensor while exposing the first reference gas sensor to a gas mixture comprising a predetermined concentration of the second gas species in the presence of a fixed concentration of the first gas species; d) repeating step c) for a number of different concentrations of the second gas species; e) determining coefficients of a first functional relationship relating the first reference gas sensor output to the concentrations of the first gas species and the second gas species, wherein the first functional relationship includes the summation of a first term and a second term, the first term being proportional to the inverse hyperbolic sine of the product of a first coefficient and the concentration of the first gas species in the gas mixture and the second term being proportional to the inverse hyperbolic sine of the product of a second coefficient and the concentration of the second gas species in the gas mixture, using the measured first reference gas sensor outputs and gas mixture concentrations from steps a) and c); and f) storing a representation of the first functional relationship determined in step e) in a non-transitory computer-readable medium that is part of or readable by the sensor processor controller; wherein the number of repetitions of steps a) and c) is chosen such that the representation of the first functional relationship represents the response characteristics of the first reference gas sensor to a predetermined level of accuracy.