Meeting: TSGS4_135_India | Agenda Item: 7.8
[FS_ULBC] Discussion on Audio Bandwidth for ULBC
vivo, Samsung, MediaTek Inc., Bytedance, Nokia, Xiaomi, Spreadtrum
pCR
Agreement
This document provides a technical discussion on the audio bandwidth design constraints for the Ultra-Low Bitrate Codec (ULBC) [1]. As 3GPP is to define in this work the requirements for a codec intended for extremely constrained environments, mainly on satellite (GEO) communications, it is crucial to prioritize design choices that maximize robustness and efficiency. Recent discussions have considered possible mandating Wideband (WB) and Super-Wideband (SWB) support for ULBC [2]. However, we argue that for the target use cases, mandatory support for Narrowband (NB) is essential, while whether wider bandwidths should be considered further enhancements of this baseline. This paper synthesizes key technical arguments and presents new experimental data to support a design philosophy focusing on performance in the most challenging conditions.
| TDoc | S4-260157 |
| Title | [FS_ULBC] Discussion on Audio Bandwidth for ULBC |
| Source | vivo, Samsung, MediaTek Inc., Bytedance, Nokia, Xiaomi, Spreadtrum |
| Agenda item | 7.8 |
| Agenda item description | FS_ULBC (Study on Ultra Low Bitrate Speech Codec) |
| Doc type | pCR |
| For action | Agreement |
| Abstract | This document provides a technical discussion on the audio bandwidth design constraints for the Ultra-Low Bitrate Codec (ULBC) [1]. As 3GPP is to define in this work the requirements for a codec intended for extremely constrained environments, mainly on satellite (GEO) communications, it is crucial to prioritize design choices that maximize robustness and efficiency. Recent discussions have considered possible mandating Wideband (WB) and Super-Wideband (SWB) support for ULBC [2]. However, we argue that for the target use cases, mandatory support for Narrowband (NB) is essential, while whether wider bandwidths should be considered further enhancements of this baseline. This paper synthesizes key technical arguments and presents new experimental data to support a design philosophy focusing on performance in the most challenging conditions. |
| Release | Rel-20 |
| Specification | 26.94 |
| Version | 0.4.0 |
| Related WIs | FS_ULBC |
| download_url | https://www.3gpp.org/ftp/tsg_sa/WG4_CODEC/TSGS4_135_India/Docs/S4-260157.zip |
| For | Agreement |
| Spec | 26.94 |
| Type | pCR |
| Contact | Wang Dong |
| Uploaded | 2026-02-03T13:43:09.967000 |
| Contact ID | 107237 |
| TDoc Status | noted |
| Is revision of | S4-251794 |
| Reservation date | 03/02/2026 12:37:15 |
| Agenda item sort order | 20 |