Non-Field-of-View Acoustic Target Estimation in Complex Indoor Environment

This paper presents a new approach which acoustically localizes a mobile target outside the Field-of-View (FOV), or the Non-Field-of-View (NFOV), of an optical sensor, and its implementation to complex indoor environments. In this approach, microphones are fixed sparsely in the indoor environment of concern. In a prior process, the Interaural Level Difference (ILD) of observations acquired by each set of two microphones is derived for different sound target positions and stored as an acoustic cue. When a new sound is observed in the environment, a joint acoustic observation likelihood is derived by fusing likelihoods computed from the correlation of the ILD of the new observation to the stored acoustic cues. The location of the NFOV target is finally estimated within the recursive Bayesian estimation framework. After the experimental parametric studies, the potential of the proposed approach for practical implementation has been demonstrated by the successful tracking of an elderly person needing health care service in a home environment.