A Fast Algorithm for Real-time Adaptive Notch Filtering

  • Kim, Haeng-Gihl (Dept. of Electronic Communication Eng., Yosu University)
  • Published : 2003.12.01


A new algorithm is presented for adaptive notch filtering of narrow band or sine signals for embedded among broad band noise. The notch filter is implemented as a constrained infinite impulse response filter with a minimal number of parameters, Based on the recursive prediction error (RPE) method, the algorithm has the advantages of the fast convergence, accurate results and initial estimate of filter coefficient and its covariance is revealed. A convergence criterion is also developed. By using the information of the noise-to-signal power, the algorithm can self-adjust its initial filter coefficient estimate and its covariance to ensure convergence.


Adaptive Notch Filter;Recursive Prediction Error (RPE);convergence and covariance


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