A New Method for Initializing Real Second Order IIR Notch Filters

This paper introduces a new method for initializing a digital real second order IIR notch filter at two frequencies. It requires only the first received sample to initialize the filter´s internal memories to their steady state values. The new method is suitable for filters used for detecting signals in the presence of strong clutter. The novelty of the new initialization lies in the fact that it does not change the implementation structure of the filter. Also, the new technique can operate in real time while offering similar performance to other techniques that require batch processing such as the projection initialization.