A method for signal detection with a gas analysis system (1, 1′) includes a radiation source (3); a gas measuring section (9) containing gas to be measured; a Fabry-Perot interferometer (13); a thermal sensor (17) configured to cause a change in voltage between electrodes with electromagnetic radiation falling thereon and arranged such that radiation released by a second interferometer mirror falls on the thermal sensor. The method includes irradiating the gas measuring section with radiation source radiation, continuously increasing or decreasing a distance of interferometer mirrors during a generating of time signal pulses at a constant period of time from one another. After a predefined number of time signal pulses, the voltage generated between the electrodes is detected and stored as a measured signal value. After a further predefined number of time signal pulses, the voltage generated between the electrodes is detected again and stored as a measured signal value.