Abstract: The invention relates to a system and method for analyzing a fluctuating flow of a mixture of gases having an optionally variable frequency. The system can be used to determine momentary presence and quantity of at least one selected gaseous component in the fluctuating flow. The system uses at least one electronic sensor adapted to generate a measurement signal representative of at least one of the presence and quantity of the at least one gaseous component. The at least one electronic sensor has a response rate slower than the frequency of the fluctuating flow and the measurement signal is subjected to a correction to construct a momentary corrected signal that equals, or at least closely resembles, at least one of the momentary presence and quantity of the at least one gaseous component. In particular the correction includes a compilation of inverse filtering and moving average filtering.