REDUCTION OF DIFFUSE NOISE IN MOBILE AND VEHICULAR APPLICATIONS - DSP for In-Vehicle and Mobile Systems - page 167

5. CONCLUSION

Experimental results confirm the diffuse model for most noise fields in
vehicular and mobile applications. In this research, we evaluated the
performance of a hybrid subband adaptive and Wiener filtering structure for
noise reduction in diffuse fields.
The hybrid system benefits from the advantages of adaptive filters in
coherent bands and also utilizes the Wiener filter to remove uncorrelated
components. By first improving the SNR as best as possible through
correlated noise reduction using subband adaptive filtering, the inherent
artifacts of standard Wiener filtering are considerably reduced.
Objective and subjective assessments confirm the superiority of the
hybrid system for noise reduction in different real-life vehicular and mobile
fields. Considering the spectral characteristics of the employed noises, it is
clear that there are larger improvements for lowpass noise sources
particularly at low SNRs.

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