Localization based on enhanced low frequency interaural level difference
This addresses localization issues for hearing-impaired people, but it is incremental as it builds on existing beamforming methods with specific modifications.
The paper tackled the problem of poor low-frequency interaural time difference processing in hearing-impaired individuals by replacing these with enhanced interaural level differences using a beamformer, resulting in improved localization for normal-hearing listeners in anechoic scenes but not in reverberant ones.
The processing of low-frequency interaural time differences is found to be problematic among hearing-impaired people. The current generation of beamformers does not consider this deficiency. In an attempt to tackle this issue, we propose to replace the inaudible interaural time differences in the low-frequency region with the interaural level differences. In addition, a beamformer is introduced and analyzed, which enhances the low-frequency interaural level differences of the sound sources using a near-field transformation. The proposed beamforming problem is relaxed to a convex problem using semi-definite relaxation. The instrumental analysis suggests that the low-frequency interaural level differences are enhanced without hindering the provided intelligibility. A psychoacoustic localization test is done using a listening experiment, which suggests that the replacement of time differences into level differences improves the localization performance of normal-hearing listeners for an anechoic scene but not for a reverberant scene.