The influences of path characteristics on multichannel feedforword active noise control system

In this paper, a new analysis method for the performance of multiple channel feedforward active noise control (ANC) system in frequency domain is proposed. The reference paths from original sources to reference sensors and the secondary paths are considered when reference sensors cannot be installed close to the original sources. A closed expression of eigenvalues of spectral density matrix is given to determine the fixed step size. The convergence performance of the ANC algorithm is analyzed in detail, and the result shows that the reference paths and the secondary paths determined by the position of the reference sensors, loudspeakers and error sensors are the main factors to the final performance. Four impulse responses measured in a real laboratory are used in the simulations to verify the conclusions.