ACOUSTICAL PROPERTIES OF AIRCRAFT NOISE MEASURED BY TEMPORAL AND SPATIAL FACTORS

Acoustical properties of aircraft noise were investigated by means of temporal and spatial factors in sound fields based on the model of auditory–brain system (see reference [10]). The model consists of the autocorrelation and crosscorrelation mechanisms for sound signals arriving at two ears and the specialization of human cerebral hemisphere. There are four temporal factors extracted from the autocorrelation function (ACF): (1) sound energy Φ (0); (2) effective duration of ACF, τe; (3) delay time of the first peak, τ1; and (4) its amplitude φ1. From the interaural crosscorrelation function (IACF), three spatial factors are extracted as (1) magnitude of the interaural crosscorrelation IACC (2) interaural delay time at IACC,τIACC , and (3) width of the maximum peak of the IACF, WIACC. It is found that the acoustical properties are well represented by the factors extracted from the ACF and the IACF.