Evaluation and demonstration of advanced active noise control in a passenger automobile

You are here: Homepage > Search

Evaluation and demonstration of advanced active noise control in a passenger automobile

Park, C. / Fuller, C. / Kidner, M.

This paper has presented the results for applying a large dimensional architecture to actively attenuate broadband road noise in a passenger automobile. Experimental and semi-empirical techniques were used to study the vehic1e characteristics and develop a suitable control system architecture. The system has not yet been evaluated in on-road trials, however, performance of the system has been evaluated in time domain simulations. The process of developing the control system architecture has illustrated same key issues and analysis techniques. A survey of the interior acoustic environment has revealed a highly damped acoustic response. Thus, low frequency performance is not expected to be sensitive to actuator and error sensor placement. Suitable attenuation of broadband noise will require many more reference sensors than suggested by principle component analysis of the disturbance source. This is due to the strong variation with frequency of sensor signal participation in the singular vectors of the disturbance spectrum. Multiple coherence analysis, which uses disturbance and performance information, is a good tool for determining the number of reference sensors. Least mean square time domain system identification is used as method for evaluating causality constraints on system performance without the complexity of actuation, or secondary path dynamics. Thus, selection of reference sensor may be accomplished independent of actuation issues. Finally, a multiple DSP control system has been validated and is expected to achieve between 4 and 10 dB of noise attenuation inside the target vehicle over the design frequency band.