Multiple-harmonic amplitude and phase control method for active noise and vibration reshaping

With the development of active noise and vibration control technology, there are increasing demands for active noise and vibration reshaping (ANVR) other than cancellation in the fields of active sound quality control, psychoacoustics, medical devices, military equipment, etc. The active noise equalizer (ANE) is one of the most popular ANVR methods. However, the ANE only controls (scales) the amplitude of the residual noise without considering the control of phase, and is unable to control frequency components that are excluded in primary noise. In this paper, we propose a more general and effective algorithm, called amplitude and phase control (APC), for ANVR, which can control amplitude and phase, simultaneously, of any interesting frequency component of the residual noise. Firstly, a modified active noise equalizer (MANE) algorithm with improved convergence is proposed based on the reference amplitude normalization and structure modification. Then, the APC algorithm is derived based on the MANE algorithm. Furthermore, numerical simulations and analytical investigations of the APC algorithm are conducted. Finally, case studies using experimental data are carried out. The multiple-harmonic primary noise was measured from a rotor test-platform and the secondary path model was identified according to a random vibration test on a shell structure. The results further verify the validity and robustness of the proposed APC algorithm.