Patent ID: 7586094

Claim:
A method comprising: receiving, at one or more processors, data quantifying a target absorption of light in a gas sample at a target wavelength and a reference absorption of light in the gas sample at a reference wavelength, the gas sample comprising a target analyte and a background reference analyte, the target analyte having a resolvable target spectral feature at the target wavelength, the background reference analyte having a resolvable background spectral feature at the reference wavelength and also an interfering background spectral feature at the target wavelength; calculating, using at least one of the one or more processors, an inferred background reference analyte absorption of the background reference analyte at the target wavelength using a background gas adjustment factor that relates the reference absorption at the reference wavelength to light absorption at the target wavelength that is due to the background reference analyte; and calculating, using at least one of the one or more processors, a target analyte concentration in the gas sample by adjusting the target absorption using the inferred background reference analyte absorption to determine a calculated target analyte absorption at the target wavelength.