Patent ID: 7031861

Claim:
A gas composition analyzer comprising: a measurement cell having an interior adapted to receive a gas composition therein; a resistance thermometer thermally coupled to the interior of said measurement cell; an acoustic meter acoustically coupled to the interior of said cell for measuring a velocity of acoustic energy transmitted between components of said acoustic meter within said cell; a reference thermometer thermally coupled to the interior of said cell for generating, during a calibration procedure, a first reference temperature value of said gas composition at a first temperature; said acoustic meter being operable during said calibration procedure to obtain an acoustic velocity-related measurement in said gas composition in said cell at a second temperature for use in generating a second reference temperature value; and a calibration unit supplied with said first and second temperature values and said acoustic velocity-related measurement for determining a calibration relationship for the temperature thermometer from the first and second reference temperature values and from measurement values of the first and second temperatures supplied by the resistance thermometer.