Proceedings ArticleDOI
Adaptive noise reduction in aircraft communication systems
P. Darlington,P. Wheeler,G. Powell +2 more
- Vol. 10, pp 716-719
TLDR
A theoretical prediction of the maximum noise reduction given by a single channel noise cancelling system controlling a group of independantly excited noise transmission paths is presented.Abstract:
It has been reported that the application of broadband noise cancelling techniques to the control of aircraft cockpit noise pickup is only successful at low frequencies This effect is explained in terms of measures of the noise transmission across a standard British oxygen mask and a discussion of the spatial characteristics of the cockpit's acoustic field A theoretical prediction of the maximum noise reduction given by a single channel noise cancelling system controlling a group of independantly excited noise transmission paths is presentedread more
Citations
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Journal ArticleDOI
Speech recognition in adverse environments
TL;DR: This paper reviews several promising methods that were proposed in the past few years to deal with the problem of automatic speech recognition in an adverse environment, discussing methods or algorithms in six categories: signal enhancement preprocessing; special transducer arrangements; noise masking; stress compensation; robust distortion measures; and novel speech representations.
Journal ArticleDOI
Performance of feedforward and feedback systems for active control
Stephen J. Elliott,T.J. Sutton +1 more
TL;DR: A consistent framework is presented for the calculation of the optimal performance of feedforward and feedback control systems in attenuating random disturbances and the robustness of the stability of such a feedback controller to changes in the plant response is assessed.
Journal ArticleDOI
Acoustic noise analysis and speech enhancement techniques for mobile radio applications
Neviano Dal Degan,Claudio Prati +1 more
TL;DR: In this article, the authors examined speech enhancement techniques to be applied in a mobile radio environment and compared the performance of a noise-cancelling microphone approach and signal processing methods.
Journal ArticleDOI
Speech enhancement for mobile telephony
M.M. Goulding,J.S. Bird +1 more
TL;DR: In this paper, a simple delay-equalized near-field array of directional microphones is analyzed and found to be effective for increasing the signal-to-noise density ratio (SNR) and reducing the reverberant distortion of the speech, without introducing any further distortion.
Proceedings ArticleDOI
Adaptive noise reduction in aircraft communication systems
TL;DR: Spectral analysis of the data showed that the diffuseness of the ambient noise fieid, along With the microphone characteristics, has a significant effect on the performance of adaptive noise cancellation.
References
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Journal ArticleDOI
Use of coherence and phase data between two receivers in evaluation of noise environments
TL;DR: In this paper, a simple illustration is presented where the acoustic field in the test section of a wind tunnel is evaluated by modelling the field as a combination of diffuse noise due to the boundary layer turbulence and propagating noise generated by the tunnel fan.
Proceedings ArticleDOI
Adaptive noise cancellation in a fighter cockpit environment
TL;DR: It is demonstrated that good (>10 dB) cancellation of the additive noise and little speech distortion can be achieved by having the reference microphone attached to the outside of the facemask and by updating the filter coefficients only during silence intervals.