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Binaural sound localizer for azimuthal movement detection based on diffraction.

Kim K, Choi A - Sensors (Basel) (2012)

Bottom Line: The gradient analysis of the ILD between the structured and unstructured microphone demonstrates the rotation directions as clockwise, counter clockwise, and no rotation of the sound source.Acoustic experiments with different types of sound source over a wide range of target movements show that the average true positive and false positive rates are 67% and 16%, respectively.Spectral analysis demonstrates that the low frequency delivers decreased true and false positive rates and the high frequency presents increases of both rates, overall.

View Article: PubMed Central - PubMed

Affiliation: Division of Electronics & Electrical Engineering, Dongguk University-Seoul, Seoul 100-715, Korea. kwkim@dongguk.edu

ABSTRACT
Sound localization can be realized by utilizing the physics of acoustics in various methods. This paper investigates a novel detection architecture for the azimuthal movement of sound source based on the interaural level difference (ILD) between two receivers. One of the microphones in the system is surrounded by barriers of various heights in order to cast the direction dependent diffraction of the incoming signal. The gradient analysis of the ILD between the structured and unstructured microphone demonstrates the rotation directions as clockwise, counter clockwise, and no rotation of the sound source. Acoustic experiments with different types of sound source over a wide range of target movements show that the average true positive and false positive rates are 67% and 16%, respectively. Spectral analysis demonstrates that the low frequency delivers decreased true and false positive rates and the high frequency presents increases of both rates, overall.

No MeSH data available.


(a) Computer screenshot. (b) Acoustic experiment in anechoic chamber.
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f11-sensors-12-10584: (a) Computer screenshot. (b) Acoustic experiment in anechoic chamber.

Mentions: In the RDD experiments, the two microphones are arranged to be parallel in the anechoic chamber and one of the receivers is installed with the RDD structure as shown in Figure 11(b). Since the azimuthal movement of the target is derived from the RDD structure rotation only, the horizontal configuration of the reference microphone is also provide the identical situation as the vertical arrangement shown Figure 6(a). The speaker emits the whitened noise signal with envelope, which simulates the time varying radial position of the sound source. The computer software (Cakewalk; Sonar VS) and the audio device (Cakewalk; Sonar V-Studio 100) have the capability to control the level of output signal by placing the track envelope that manipulates the motorized volume fader. The envelope graph is derived from the inverse square law with logarithm function and applied to the specific output track. While the azimuthal movement of the RDD structure is executed by the human operator, visual supervision is performed for improved angular control by using the wireless video camera. Figure 11(a) shows the computer screenshot, which visualizes the audio software and top-view RDD structure. The real-time visual feedback of the DoA angle fulfills the coarse manipulation of angular velocity for the given experimental interval.


Binaural sound localizer for azimuthal movement detection based on diffraction.

Kim K, Choi A - Sensors (Basel) (2012)

(a) Computer screenshot. (b) Acoustic experiment in anechoic chamber.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472845&req=5

f11-sensors-12-10584: (a) Computer screenshot. (b) Acoustic experiment in anechoic chamber.
Mentions: In the RDD experiments, the two microphones are arranged to be parallel in the anechoic chamber and one of the receivers is installed with the RDD structure as shown in Figure 11(b). Since the azimuthal movement of the target is derived from the RDD structure rotation only, the horizontal configuration of the reference microphone is also provide the identical situation as the vertical arrangement shown Figure 6(a). The speaker emits the whitened noise signal with envelope, which simulates the time varying radial position of the sound source. The computer software (Cakewalk; Sonar VS) and the audio device (Cakewalk; Sonar V-Studio 100) have the capability to control the level of output signal by placing the track envelope that manipulates the motorized volume fader. The envelope graph is derived from the inverse square law with logarithm function and applied to the specific output track. While the azimuthal movement of the RDD structure is executed by the human operator, visual supervision is performed for improved angular control by using the wireless video camera. Figure 11(a) shows the computer screenshot, which visualizes the audio software and top-view RDD structure. The real-time visual feedback of the DoA angle fulfills the coarse manipulation of angular velocity for the given experimental interval.

Bottom Line: The gradient analysis of the ILD between the structured and unstructured microphone demonstrates the rotation directions as clockwise, counter clockwise, and no rotation of the sound source.Acoustic experiments with different types of sound source over a wide range of target movements show that the average true positive and false positive rates are 67% and 16%, respectively.Spectral analysis demonstrates that the low frequency delivers decreased true and false positive rates and the high frequency presents increases of both rates, overall.

View Article: PubMed Central - PubMed

Affiliation: Division of Electronics & Electrical Engineering, Dongguk University-Seoul, Seoul 100-715, Korea. kwkim@dongguk.edu

ABSTRACT
Sound localization can be realized by utilizing the physics of acoustics in various methods. This paper investigates a novel detection architecture for the azimuthal movement of sound source based on the interaural level difference (ILD) between two receivers. One of the microphones in the system is surrounded by barriers of various heights in order to cast the direction dependent diffraction of the incoming signal. The gradient analysis of the ILD between the structured and unstructured microphone demonstrates the rotation directions as clockwise, counter clockwise, and no rotation of the sound source. Acoustic experiments with different types of sound source over a wide range of target movements show that the average true positive and false positive rates are 67% and 16%, respectively. Spectral analysis demonstrates that the low frequency delivers decreased true and false positive rates and the high frequency presents increases of both rates, overall.

No MeSH data available.