EBEN: Extreme bandwidth extension network applied to speech signals captured with noise-resilient body-conduction microphones
Julien Hauret, Thomas Joubaud, Véronique Zimpfer, Éric Bavu
TL;DR
Body-conduction microphone speech suffers from ambient noise and reduced bandwidth, limiting intelligibility. EBEN introduces a GAN-based extreme bandwidth extension network that uses an $M$-band PQMF decomposition and a U‑Net‑like generator to reconstruct wideband speech in real time, aided by a multiscale ensemble of subband discriminators. The model balances adversarial and reconstruction losses to preserve realism while recovering missing high-frequency content. Experiments on simulated in-ear degradations show competitive objective metrics and strong subjective scores, with a lightweight, edge-friendly architecture suitable for real-time deployment and potential public dataset release.
Abstract
In this paper, we present Extreme Bandwidth Extension Network (EBEN), a Generative Adversarial network (GAN) that enhances audio measured with body-conduction microphones. This type of capture equipment suppresses ambient noise at the expense of speech bandwidth, thereby requiring signal enhancement techniques to recover the wideband speech signal. EBEN leverages a multiband decomposition of the raw captured speech to decrease the data time-domain dimensions, and give better control over the full-band signal. This multiband representation is fed to a U-Net-like model, which adopts a combination of feature and adversarial losses to recover an enhanced audio signal. We also benefit from this original representation in the proposed discriminator architecture. Our approach can achieve state-of-the-art results with a lightweight generator and real-time compatible operation.
