Ambulance Siren Noise Reduction Using Virtual Sensor Based Feedforward ANC System

Acoustic noise is troublesome to people in general and to patients in particular. When the patient in critical condition is being shifted to the hospital in an ambulance, he is exposed to continuous noise of siren. The patient feels irritation as well as anxiety especially if he is cardiac patient. Active noise control system is used to suppress the unwanted noise in the specific zone of silence. However sometimes it is not feasible to place error microphone in the zone of silence (ZOS) near to patient. An ambulance is one such application. In such a situation, virtual sensing technique is used for active noise control (ANC) application. In this paper, a feed forward active noise control method with virtual sensing has been proposed to reduce the ambulance siren noise for patient inside the ambulance. The simulations are done in MATLAB and reduction in noise of approximately 39dB, is obtained. This shows that ANC along with virtual sensing has significant contribution for reducing siren noise in the ambulance.