A New Active Headset for a Helicopter Application

Document type: Conference Papers
Peer reviewed: Yes
Author(s): Mathias Winberg, Sven Johansson
Title: A New Active Headset for a Helicopter Application
Conference name: SVIB AU-2 Konferens
Year: 1998
City: Riksgränsen, Sverige
Organization: Blekinge Institute of Technology
Department: Dept. of Signal Processing (Institutionen för signalbehandling)
Dept. of Signal Processing S-372 25 Ronneby
+46 455 38 50 00
Authors e-mail: mathias.winberg@its.bth.se
Language: English
Abstract: In helicopters, the low frequency noise generated by the rotors and engines often masks and jeopardizes safe communication. In addition, pilots are likely to suffer from damage to their hearing due to the high sound levels in the headset produced in compensating for the noise caused by increased loudspeaker levels. A feasible approach is to reduce the low frequency noise by using active techniques combined with a method for reducing the noise in the intercom microphone signal, with lower loudspeaker levels as a result. Helicopter noise consists of tonal components embedded in broadband noise. In order to achieve an efficient attenuation of the primary noise inside the headset, a combination of a digital feedforward controller and an analog feedback controller is employed. Spectral Subtraction is used to suppress the background noise in speech signals.
Subject: Signal Processing\Active Noise and Vibration Control
Signal Processing\Speech Enhancement