Binaural Signal Matching with Wearable Arrays for Near-Field Sources and Directional Focus

TL;DR

This paper enhances binaural signal matching for near-field sound sources using wearable arrays by incorporating distance and directional weighting, leading to improved perceptual and objective quality in near-field scenarios.

Contribution

It introduces a Field of View weighting in near-field BSM, improving robustness and performance for near-field sound reproduction with wearable arrays.

Findings

NF-BSM outperforms far-field BSM in near-field conditions

NF-FoV-BSM achieves the best perceptual and objective quality

Incorporating source distance and directional weighting improves binaural reproduction

Abstract

This paper investigates the performance of Binaural Signal Matching (BSM) methods for near-field sound reproduction using a wearable glasses-mounted microphone array. BSM is a flexible, signal-independent approach for binaural rendering with arbitrary arrays, but its conventional formulation assumes far-field sources. In our previous work, we proposed a near-field extension of BSM (NF-BSM) that incorporates distance-dependent modeling and showed improved performance over far-field BSM using analytic data, though degradation persisted for sources very close to the array. In this study, we extend that analysis by using realistic simulated data of near-field Head-Related Transfer Functions (HRTFs) and Acoustic Transfer Functions (ATFs) of the array, accounting for listener head rotation and evaluating binaural cues such as interaural level and time differences (ILD and ITD). A key contribution is the introduction of a Field of View (FoV) weighting, designed to emphasize perceptually relevant directions and improve robustness under challenging conditions. Results from both simulation and a listening test confirm that NF-BSM outperforms traditional far-field BSM in near-field scenarios, and that the proposed NF-FoV-BSM method achieves the best perceptual and objective quality among all tested methods, particularly at close source distances and under head rotation. These findings highlight the limitations for far-field models in near-field sources and demonstrate that incorporating source distance and directional weighting can significantly improve binaural reproduction performance for wearable spatial audio systems.