Abstract: A method of and device for the determination with high computational efficiency of spectrum parameters of a spectrum utilizes quantification and model fitting of sampling values of a signal in the time domain on the basis of a model function comprising exponentially damped sinusoids. The method starts with a coarse estimation of a number of spectrum parameters, followed by linearization of the model function and iterative estimation of the coarsely estimated parameters and further parameters, utilizing a least-squares optimization procedure where inner product terms are brought into analytic form and are preferably recursively determined.