Argos-3 Satellite Communication System: Implementation on the Arvor Oceanographic Profiling Floats

Abstract

The scientific community observes the ocean for applications in the fields of oceanography and climate research. To recover in situ data, more than 3000 profiling floats are operated in the framework of the Argo program. Each float performs cycles between the sea surface and a depth of 2000 m. Scientific data are gathered while the float is traveling upward from the depths of the oceans and are then transmitted via a satellite communication system at the end of each cycle. During its time at the surface, mainly dedicated to transmissions, the float is vulnerable and subject to drift, which limits its use in many studies. Moreover, transmission times are becoming longer due to a trend toward high-resolution or multisensor profiles. Consequently, the transmission system embedded in the profiling floats had to evolve. Argos-3 is the latest generation of the Argos satellite communication system. It has been designed to allow instruments to transmit more data in a small time budget and as an alternative to Iridium, already implemented on profiling floats in restrictive applications. This study aims to evaluate the implementation of Argos-3 on Arvor profiling floats. Tests were carried out first in the laboratory, before being implemented on the Arvor float and deployed at sea. This study proves that the high-data-rate mode suffered from European electromagnetic noise, which is incompatible with this application. The interactive low-data-rate mode was successfully qualified; it is capable of transmitting an entire dataset in a few minutes, compared to 8–10 h for the previous Argos-2 system.

Argo Data 1999–2019: Two Million Temperature-Salinity Profiles and Subsurface Velocity Observations From a Global Array of Profiling Floats

“…The Argos-3 satellite system was implemented on ARVOR floats for evaluation of its interactive low-and high-data-rate modes, both offering bidirectional transmission and a higher throughput than the older Argos-2 satellite system. While the low-data-rate mode offered faster data transmissions, the high-data-rate mode suffered from electromagnetic noise around Europe (André et al, 2015). At regional scales, non-global transmission systems such as BeiDou in Asia and Orbcomm in North America have also had limited use on profiling floats.…”

Design and Testing of a Kinetic Energy Harvester Embedded Into an Oceanic Drifter

“…It is planned as an undrogued drifter with GNSS (Global Navigation Satellite System) for positioning and equipped with two thermistors used for the calibration of satellite sea surface temperature data. Furthermore, ocean wave parameters will be analyzed through an IMU and the satellite communication will be ARGOS-based [26].This WAVY drifter will be equipped with a hybrid energy harvesting system consisting of a solar panel and a KEH system. TABLE I shows some mechanical parameters of the WAVY drifter.…”

Preparing the New Phase of Argo: Technological Developments on Profiling Floats in the NAOS Project

“…In the framework of NAOS, we thus studied, implemented and evaluated the Argos-3 satellitecommunication system during a pilot experiment at sea, the only one of its kind carried out at the time of writing. This section compares the results obtained at sea on profiling floats fitted with the Argos-2 (Woodward et al, 2009), Argos-3 (André et al, 2015), Iridium SBD (Short Burst Data) (MacMahon and Rathburn, 2005), and Iridium RUDICS (Router-Based Unrestricted Digital Internetworking Connectivity Solutions) (Prior-Jones, 2008) satellite-communication modes.…”

“…Profiling floats equipped with Argos-2 transmitted an average profile of 500 bytes in 8 h (outside the Mediterranean Sea, where transmission was programmed to last over 12 h due to continental electromagnetic noise), i.e., an average throughput of approximately 0.001 kByte/min. The Arvor A3 low-data-rate profiling floats are described in detail in André et al (2015). Their statistics were computed after the launch of the Saral satellite, giving rise to better results: a profile of 500 bytes was transmitted in 3 min 10 s on average, which converts into a data-transfer rate of approximately 0.16 kByte/min.…”