A measurement system (100) determines gas concentrations in a gas mixture of a gas sample by utilizing thermal conductivities and paramagnetic effects of thermal conductivities in the gas mixture involving data sets (203). A circuit arrangement provides measured values with an AC signal component and with a DC signal component to a calculation and control unit (200). An oxygen concentration in the gas mixture of the gas sample is determined based on the standardized AC signal components and a concentration of another gas in the gas mixture of the gas sample is determined based on the standardized DC voltage signal components. Output signals are generated by the calculation and control unit, which indicate the determined oxygen concentration and the determined concentration of another gas in the gas mixture of the gas sample.