Frequency-domain periodic active noise control and equalization

This paper analyzes a frequency-domain periodic active noise control (ANC) system. The adaptive filter employs the frequency domain complex least mean square (LMS) algorithm driven by a unit value at each frequency bin. The synchronously sampled frequency-domain adaptive structure acts as a comb filter to cancel narrowband noises with harmonically related frequencies. A frequency-domain periodic active noise equalization (ANE) system, which reshapes the residual noise by controlling the output of the adaptive comb filter at each frequency bin, is also developed and analyzed in this paper. Computer simulations and real-time experiments conducted attest to the practical usefulness of the proposed ANC and ANE systems