Phd Position F/m Immersive Sound and Virtual Acoustics On Distributed Fpgas

Le descriptif de l’offre ci-dessous est en Anglais_

**Type de contrat**: CDD

**Niveau de diplôme exigé**: Bac + 5 ou équivalent

**Fonction**: Doctorant

**A propos du centre ou de la direction fonctionnelle**:
The Inria research centre in Lyon is the 9th Inria research centre, formally created in January 2022. It brings together approximately 320 people in 19 research teams and research support services.

Its staff are distributed in Villeurbanne, Lyon Gerland, and Saint-Etienne.

The Lyon centre is active in the fields of software, distributed and high-performance computing, embedded systems, quantum computing and privacy in the digital world, but also in digital health and computational biology.

**Contexte et atouts du poste**:
**General Description**

The main objectives of this PhD are to:

- Design a distributed FPGA-based spatial audio system providing unparalleled computational capabilities and perfect synchronicity between all the speakers.
- Adapt and optimize spatial audio, virtual acoustics, and soundscape rendering algorithms to FPGAs to fully take advantage of their computational power.

**Context**

**Mission confiée**:
**Full PhD Topic**

Immersive 3d audio has been receiving booming interest in recent years [1]. An increasingly high number of movie theaters, concert halls, Virtual Reality (VR) platforms in museums, attractions in amusement parks, cars, etc. are equipped with advanced immersive sound systems involving a large number of speakers that can be used to render soundscapes in 3d, modify the acoustics of a room, enhance sound quality and speech intelligibility, carry out active noise cancellation, etc. The need for advanced immersive sound systems recently culminated with the opening of the “Las Vegas Sphere,” which hosts the largest and densest speaker array in the world involving a total of 167,000 amplified speakers [2].

Managing a large number of individual audio channels in real-time requires a tremendous amount of computational power and incredibly high bandwidths, preventing systems involving a lot of speakers to be managed “collectively.” For example, in the case of the Las Vegas Sphere, speakers are organized in groups of acoustic panels which all receive the same source signal and that implement spatial audio algorithms “locally.”

The norm for managing real-time immersive 3d audio systems [3, 4] is to rely on a centralized software-based approach: a single powerful computer connected to one or multiple audio interfaces providing a limited number of audio outputs. Thus, the computer’s throughput determines the maximum number of manageable parallel digital audio streams (and applied computations), creating a hardware-related bottleneck.

Contrary to this norm, we would like to rely on a distributed computing approach leveraging the computational power of large Field-Programmable Gate Array (FPGA). In this approach, each FPGA is in charge of computing the sound of a limited set of speakers. This will allow for a very large number of speakers to be simultaneously managed at a very low cost with unparalleled latency performances.

In order to reach this goal, multiple challenges ranging from transmitting audio streams to many audio devices [5] with close to perfect synchronicity to running complex audio Digital Signal Processing (DSP) algorithms on FPGAs [6] must be tackled. For that, the work carried out within the Emeraude team on this topic during the past five years will be leveraged [7, 8, 9]. We plan to heavily rely on High-Level Synthesis (HLS) for programming FPGAs, with the Syfala tool in particular [10]. Allowing an unparalleled number of speakers to be collectively managed in the context of immersive 3d audio will open the door to the deployment of a broad range of new immersive audio techniques.

The main objectives of this PhD are to:

- Design a distributed FPGA-based spatial audio system providing unparalleled computational capabilities and perfect synchronicity between all the speakers.
- Adapt and optimize spatial audio, virtual acoustics, and soundscape rendering algorithms to FPGAs to fully take advantage of their computational power.

**References**

[1] Charles de Laubier. Le son immersif, nouveau d´efi de l’industrie musicale pour s´eduire spectateurs et auditeurs. Le Monde, May 2024.
[3] Michael Gerzon. Multi-system ambisonic. Wireless World, 83:43-47, 1977.
[4] Lauri Savioja and Peter Svensson. Overview of geometrical room acoustic modeling techniques. The Journal of the Acoustical Society of America, 138(2):708-730, 2015.
[5] Pierre Cochard, Jurek Weber, Romain Michon, Tanguy Risset, and Stéphane Letz. Ethernet real-time audio transmission to FPGA. In Proceedings of the 5th IEEE International Symposium on the Internet of Sounds, Erlangen, Germany, 2024.
[6] Maxime Popoff. Compilation of Real-Time Audio DSP on FPGA. Phd thesis, INSA Lyon, Lyon, France, January 2025.
[7] Thomas Rushton, Romain Michon, and Tanguy Risset. All together now: A synchronou