Recursive Closed-Form Optimization of Spectral Audio Power Allocation for Near End Listening Enhancement

Abstract:
In mobile telephony, near end listening enhancement is desired by the near end listener who perceives not only the clean far end speech but also ambient background noise. A typical scenario is mobile telephony in acoustical background noise such as traffic or babble noise. In such a situation, it is often not acceptable/possible to increase the audio power. In this contribution we analyse the calculation rules of the Speech Intelligibility Index (SII) and develop a recursive closed-form solution which maximizes the SII under the constraint of an unchanged average power of the audio signal. This solution has very low complexity compared to a previous approach of the authors and is thus suitable for real-time processing.