Conference Paper
Automotive Microphone Performance: from Specification to User Experience
AES Conference: 2019 AES INTERNATIONAL CONFERENCE ON AUTOMOTIVE AUDIO · Paper 5 · September 2019
Abstract
This paper discusses correlations between microphone specifications defined in laboratory conditions and the perceived user experience in automotive applications such as in-car voice communication and array beamforming. Experimental recordings are obtained at various driving conditions using three common types of automotive microphones mounted in three vehicle models (Sedan, SUV and Electric). Speech intelligibility index (SII) and subjective listening based on actual in-car recordings are used to evaluate the communication quality of microphones with different specifications including frequency responses, signal-to-noise-ratios (SNR) and acoustic overload points (AOP). It is shown that, when influences of automotive application environments are considered, microphones with advanced SNR and AOP specifications do not always correlate to higher user experience such as better SII. To study effects of microphone element sensitivity and phase mismatches on beamforming performance, a simulation model is developed. It is found that the tolerance of microphone element-to-element mismatches highly depends on the chosen array processing algorithm. Results in this study could help users and designers choose proper microphone elements for automotive applications.
