# Intelligent Synchronized Long-Term Biodiversity Observatories with QHBv3

Philémon Prévot, Valentin Barchasz, Valentin Gies, Sebastian Marzetti, Hervé Glotin

► To cite this version:

Philémon Prévot, Valentin Barchasz, Valentin Gies, Sebastian Marzetti, Hervé Glotin. Intelligent Synchronized Long-Term Biodiversity Observatories with QHBv3. Journées des Jeunes Bioacousticiens 2025, Jun 2025, Vernon, Giverny, France. 2025. [hal-05165225v2](https://hal-tln.hal.science/hal-05165225v2)

HAL Id: hal-05165225

https://univ-tln.hal.science/hal-05165225v2

Submitted on 18 Jul 2025

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<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
## Introduction

Studying biodiversity in complex and diverse environments require leveraging numerous forms of data gathering. Acoustic monitoring has always been a key feature among those, allowing for precious behavior and ecosystems recording where light or storage space are sparse, especially in marine environments. The Qualilife HighBlue (QHB) v3 recorder has been designed as a scalable, synchronizable, and reliable high-frequency range acoustic recorder aimed at ecosystems long-term studies.

<figure><img src="image_2.png" /><figcaption>Fig. 1: Top view of a QHBv3 recorder</figcaption></figure>

<figure><img src="image_3.png" /><figcaption>Fig. 1: QHBv3 Block Diagram</figcaption></figure>

<figure><img src="image_4.png" /><figcaption>Fig. 2: First synchronization test setup</figcaption></figure>

<figure><img src="image_5.png" /><figcaption>Fig. 3: Bombyx3 intelligent surface buoy</figcaption></figure>

## Technical specifications

QHB high-frequency recorder features 8, 16 or 24 bits channels with accurate timestamping operating up to 512ksps each. They are implemented on up to three 2-channels daughter-boards. Those channels allow for:

* Differential input for harsh electromagnetic environments.
* Single 3.3V inputs for standard hydrophones and microphones.
* Input superposed on power supply for specific microphones.
* Compatibility with charge amplifiers for passive piezo-electric sensors connection.
* Energy Consumption:
  * Max Energy Consumption: 4W (SD and hydrophone including C75, x5 channels)
  * Min Energy Consumption: 100µW in Sleep Mode

<figure><img src="image_6.png" /><figcaption>Fig. 4: Noise spectrum in mel scale</figcaption></figure>

## Advanced features : GPS & PPS

QHB recorder is equipped with a high-frequency 3-axis MARG sensor. It is used for source direction and attitude estimation in underwater buoys and antennas. Infrared, Visible light, Temperature and Pressure sensors are also available. The card is also able to communicate information through GSM and has successfully been paired with on-the-shelf modems in ongoing projects.

Additional boards can be plugged in for task-specific features:
* A GPS-PPS antenna for on-land data recording
* An atomic clock for high-precision time recording
* A power board for hydrophones and/or microphones alimentation in case of board power perturbations

<figure><img src="image_7.png" /><figcaption>Fig. 5: GPS board</figcaption></figure>

## Current projects & deployments

To this day the QHBv3 system has been deployed for extended periods of time in diverse conditions. We can cite as examples the SYLVANIA ANR project [4], the GEPOG survey effort, and soon the BOMBYX buoys from the EUROPAM project [3]. It has produced interesting results during the WhaleWay 5 and SAM2024 missions. We can also note that the previous version, QHBv2 [1] has been deployed in various missions all over the world.

<figure><img src="image_8.png" /><figcaption>Fig. 6: Sperm whale clicks binary CNN classifier ROC</figcaption></figure>

## Offline AI inference

Simple AI models can be implemented into the QHB recording sequence for real-time detection of species of interest. Complement by acoustic indices computation gives real-time insight on the recorder's acoustic environment. Models in use are 3-layers fully connected CNNs [2], for a computational cost in $o(F^2 * T)$ where F is the number of features and T the number of samples to analyze. Their average measured inference time in use is 3s for 10s of recording at 128kHz.

<figure><img src="image_9.png" /><figcaption>Fig. 7: Source localization</figcaption></figure>

## Synchronization for Source Localization

The GPS antenna and atomic clock are used for high-precision array synchronization of on-land or underwater systems. Wide-baseline acoustic sensor arrays possibilities were demonstrated in the SYLVANIA ANR project [4] and precise cetaceans' trajectories computation is underway using WhaleWay 5 data. This feature opens the door to large sensor arrays for extensive and precise environment and individuals monitoring.

## Conclusion & Discussion

The QHBv3 recorder is a high-speed low-power accurate and precise acoustic recording system for extensive biodiversity survey. Its additional features open the door to novel wide-range synchronized sensors arrays with embedded AI detection tools. Finally its support of differential input creates the opening for very-low electromagnetic noise microphones and hydrophones. Though those features sets the QHBv3 recorder apart from its competitors there are still some area of improvements, mainly being power consumption reduction.

## Aknowledgments

Many thanks to Mathias Colin for sharing synchronization results for this poster. This work received financial support from the France 2030, PIA3 PSI-BIOM, operated by ADEME, grant 2182D0406-A. H.G. thanks ANR for grants ULPCochlea ANR-21-CE04-0020, SYLVANIA ANR-21-CE04-0019, European Biodiversa2021-488 EUROPAM 2023-2026, SeaStMar MARITTIMO IF Marittimo00081, ETHAC APOG Région Sud and DGA IAD for AI Chair ADSIL ANR-20-CHIA-0014.

## References

[1] Valentin Barchasz et al. "A Novel Low-Power High Speed Accurate and Precise DAQ with Embedded Artificial Intelligence for Long Term Biodiversity Survey".
[2] Paul Best et al. "Stereo to five-channels bombyx sonobuoys: from four years cetacean monitoring to real-time whale-ship anti-collision system".
[3] Marion Poupard et al. "Passive acoustic monitoring of sperm whales and anthropogenic noise using stereo- phonic recordings in the Mediterranean Sea, North West Pelagos Sanctuary".
[4] Stylianos Tsampourakis. "Joint localisation and diarisation of concurrent vocalisers of the Orthoptera order by PPS synchronised microphone arrays".