A New Robust Narrowband Active Noise Control System Structure with Only One Channel for Referernce Signal Filtering

In a conventional narrowband active noise control system, each reference cosine wave has to be filtered by an estimate of the secondary-path. We call this part x-filtering block. The number of x-filtering blocks is equal to the number of targeted frequencies. The computational cost of the system due to the x-filtering operations may form a bottleneck in real system implementation. In this paper, we propose a new narrowband ANC system structure which requires only one xfiltering block regardless of q. All the cosine waves are combined as an input to a x-filtering block whose output is decomposed by an efficient bandpass filter bank into filtered cosine waves for the FXLMS that follows. As a result, the computaional cost of the system is considerably reduced. The new structure is further implanted in a recently developed ANC system that is capable of mitigating the frequency mismatch (FM). Simulations demonstrate that the new systems present robust performance very similar to that of their counterparts, but enjoy considerable advantages in system implementation.