The effectiveness of an active noise control system with remote microphones technique in a tractor cabin1

This paper presents a preliminary study of an active noise control (ANC) system implemented on a tractor cabin. This system employs a multi-channel feedforward configuration, with two error microphones and two control loudspeakers positioned in the cabin and an external reference microphone. Furthermore, the system implements the remote microphone technique (RMT), which allows to place the error microphones at a given distance from the region where the quiet zone is to be created, in this case around a head used for binaural measurements. To evaluate the effectiveness of the ANC system, simulated narrowband and broadband disturbance signals are generated through an acoustic source external to the cabin. Despite a reduction in the performance compared to the case without the RMT, caused by internal modelling of the signals, the developed system demonstrates its potentiality for a real application, where the error microphones cannot be left close to the region where noise has to be cancelled.