Accession Number : ADA289422

Title :   Head Related Transfer Function Approximation Using Neural Networks.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Millhouse, John K.

PDF Url : ADA289422

Report Date : DEC 1994

Pagination or Media Count : 156

Abstract : This thesis determines whether an artificial neural network (ANN) can approximate the Armstrong Aerospace Medical Research Laboratories (AAMRL) head related transfer functions (HRTF) data obtained from research at AAMRL during the fall of 1988. The first test determines whether HRTF lends any support in sound localization when compared to no HRTF (Interaural Time Delay only). There is a statistically significant interaction between the location of the sound and whether the HRTF or no HRTF is used. When this interaction is removed using the alternate F.Value, the statistics give the result of equal means for the filters and azimuth. This means that at certain angles of azimuth, the HRTF either provides no advantage at all or hinders localization capabilities. Adding in the corrections for reversals changes the results to where the means of the azimuth are not statistically equal. The reversal corrections will inherently reduce the error results. However, comparing the number of reversals indicates an advantage of using the HRTF over no HRTF. The second test determines whether HRTF and ANN lend the same amount of information in sound localization when compared to each other. With reversal corrections included, a statistical advantage is not indicated, and the means of the two filters are statistically equal. Also there is a statistically significant interaction between the location of the sound and whether the AAMRL HRTF or ANN HRTF is used. Comparing the number of reversals does not indicate a large difference between the AAMRL HRTF and the RBF HRTF.

Descriptors :   *NEURAL NETS, *ARTIFICIAL INTELLIGENCE, ALGORITHMS, SIGNAL PROCESSING, DATA PROCESSING, ANGLES, EXPERIMENTAL DATA, TRANSFER FUNCTIONS, BRAIN, MULTIVARIATE ANALYSIS, COMPARISON, ANALYSIS OF VARIANCE, THESES, THREE DIMENSIONAL, SOUND WAVES, AZIMUTH, HEAD(ANATOMY), ERROR CORRECTION CODES, EAR, AUDITORY SIGNALS, AUDITORY ACUITY, AUDITORY PERCEPTION.

Subject Categories : Cybernetics
      Anatomy and Physiology
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE