Real-time hearing assessment device based on distortion product otoacoustic emissions

Real-time implementation of a recently introduced method of measurement of distortion product otoacoustic emissions (DPOAEs) for hearing assessment is presented. Development of the real-time application begins with the discretization of the DPOAE estimation algorithm in Matlab and then programming in C for final downloading onto a digital signal processor (DSP) platform. Aside from the signal processing task involved in the estimation process, the DSP platform controls a microphone/speaker system, which generates the acoustical stimuli for presentation to the ear canal and collects the acoustical responses recorded in the ear canal. The real-time results are compared with those obtained by a continuous-time off-line model of the DPOAE estimation algorithm. The developed DPOAE measurement system offers a high degree of noise immunity and a short measurement time, both of which are of importance in clinical applications of the DPOAE signals.