A New Passive/Active Hybrid Headset for a Helicopter Application
| Document type: | Journal Articles |
|---|---|
| Article type: | Original article |
| Peer reviewed: | Yes |
| Author(s): | Mathias Winberg, Sven Johansson, Thomas L Lagö, Ingvar Claesson |
| Title: | A New Passive/Active Hybrid Headset for a Helicopter Application |
| Journal: | International Journal of Acoustics and Vibration |
| Year: | 1999 |
| Volume: | 4 |
| Issue: | 2 |
| ISSN: | 1027-5851 |
| Publisher: | Int. Inst. of Acoustics and Vibration (IIAV) |
| Organization: | Blekinge Institute of Technology |
| Department: | Department of Telecommunications and Signal Processing (Institutionen för telekommunikation och signalbehandling) Department of Telecommunications and Signal Processing S-372 25 Ronneby +46 455 38 50 00 |
| Authors e-mail: | sjo@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 to overcome the noise caused by increased speaker 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 speaker 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. This paper evaluates a combination of the two techniques and their application to real data. |
| Subject: | Signal Processing\Active Noise and Vibration Control Signal Processing\Speech Enhancement |
| Keywords: | active noise control, headset, feedforward control, feedback control, speech enhancement, spectral subtraction |
