Adaptive cancellation of a periodic interference using the HGLS adaptation algorithm

A proposal of a hyperstable gradient least squares (HGLS) adaptive recursive filter is presented in this paper. The adaptive recursive filter stability is guaranteed during the adaptation process according to the hyperstability theorem. The HGLS algorithm is used to update the coefficients of the adaptive noise canceller to remove periodic interference that is combined with desired signals. The HGLS adaptive noise canceller provides significant improvements in the output signal to noise ratio for a wide spectrum of the interference signals.