A Novel Approach to Active Noise Control using Normalized Clipped Adaptive Algorithm

In this paper, an efficient normalization based adaptive algorithm is used for active noise control in mechanical systems in order to reject extensive disturbances. The proposed implementations are suitable in applications like various motors, generators, aircrafts, battle field and elevators, etc where noise reduction is very important. In the experiments, the authors used several variants of the familiar Filtered X Least Mean Square (FXLMS) algorithm. In FXLMS the vector of past inputs is first filtered by the secondary path transfer function, hence it is named as filtered X LMS. These modified results normalized FXLMS (NFXLMS) and normalized clipped FXLMS (NCFXLMS) algorithms, leads to fast convergence, better noise rejection capability. The NCFXLMS algorithm requires only half of the multiplications requires than NFXLMS. This type of low complexity strategy is not used in active noise control application in mechatronic systems. Simulation results prove that the proposed active noise cancellers provide better performance in terms of signal to noise ratio than the conventional FXLMS.