The invention proposes a method of processing a noisy digital time signal yk corresponding to an initial time signal xt after having been conditioned by a conditioning chain, the said initial signal xt representing information about radiations coming from a radiation source, these radiations having an energy distribution, characterised in that a state model is implemented, representing the conditioning imposed by the said chain to pass from the initial time signal xt to the noisy digital time signal yk in order to obtain from the noisy digital time signal yk a non-noisy digital estimate signal of the initial time signal xt. The invention furthermore proposes a system capable of implementing said method.