Saturday, May 27, 2017
      CMRE Facebook page  CMRE LinkedIn page  CMRE PAO Youtube page
   
Text Size
CMRE banner

Memorandum Reports

Report that covers interim results during the course of a project. Note: Unless linked to the full text, reports are only available to NATO member nations from designated distribution centres.

Documents

Order by : Name | Date | Hits [ Ascendant ]

Combined analysis of LOGMEC16 oceanographic glider and satellite data and their correlation Combined analysis of LOGMEC16 oceanographic glider and satellite data and their correlation

new!
Date added: 05/23/2017
Date modified: 05/23/2017
Filesize: Unknown

Combined analysis of LOGMEC16 oceanographic glider and satellite data and their correlations. Borrione, Ines; Oddo, Paolo; Russo, Aniello; Coelho, Emanuel. CMRE-MR-2017-003. April 2017.

During the LOGMEC16 (Long-Term Glider Mission for Environmental Characterisation) sea trial carried out in the eastern Ligurian Sea (North-western Mediterranean Sea), two oceanographic gliders rated to a maximum depth of 1000m were operating continuously from 3 May to 27 June 2016. When possible, glider tracks were synchronised with the footprints of contemporaneous altimeters (i.e., Jason 2, SARAL/AltiKa and CryoSat-2). Temperature and salinity measured by the gliders that were co-localised with the altimeter passages, were used to calculate along-track dynamic heights. The latter were then compared with the near-real time absolute sea level CMEMS-TAPAS (Copernicus Marine Environment Monitoring Service - Tailored Altimetry Products for Assimilation Systems) product. Where available, the CMEMS near-real time 1 km resolution, Aqua-MODIS ocean colour data was also used as a tracer of the main oceanographic features of the region. Comparison between SLA derived from gliders and TAPAS along common transects, shows that patterns, variability, and scales in the filtered SLA are comparable to those obtained from glider measurements. Differences are mostly explained by the fact that gliders have sampled at different times the same structures, which were moving northwards at ~ 0.16 m s-1. Conversely, the unfiltered SLA shows a variability that is not fully captured by the in situ measurements. Both gliders and SLA provide evidence of mesoscale variability (i.e., meanders) likely due to the baroclinic instability of the Northern Current. The scales of these structures (i.e., amplitude of 39 km, and propagation speed of 0.16 m s-1) are in agreement with those previously described in literature, and are confirmed by the larger scale ocean colour measurements.

ISR Implementation of ocean optics protocols to estimate spectral absorption coefficients of particles, suspended matters and phytoplankton pigments in ALOMEx'15 water samples: results and comparisons with satellite measurements ISR Implementation of ocean optics protocols to estimate spectral absorption coefficients of particles, suspended matters and phytoplankton pigments in ALOMEx'15 water samples: results and comparisons with satellite measurements

Date added: 04/24/2017
Date modified: 04/24/2017
Filesize: Unknown

ISR Implementation of ocean optics protocols to estimate spectral absorption coefficients of particles, suspended matters and phytoplankton pigments in ALOMEx'15 water samples: results and comparisons with satellite measurements. Pennucci, Giuliana; Sanjuan Calzado, Violeta. CMRE-MR-2016-021. March 2017.

One of the main requirements for a comprehensive characterisation of water column optical properties is the simultaneous acquisition of physical and biological parameters that are traditionally observed using satellites, laser systems, ships and moorings, especially in dynamic areas. The Atlantic Lidar Optical Measurements Experiment 2015 (ALOMEx'15), conducted from 31 October to 12 November 2015 the Alboran Sea and Sahara Upwelling, provided an attempt at determining in situ measurement uncertainties by comparing instrument specific calibrations and measurement protocols. In this context, two different topics have been addressed in this report: (1) post- processing algorithms development to analyse optical water column properties and (2) data comparison and validation using satellite imagery. Specifically, introduction and conventions are provided in the first part of this document (Sections 1 and 2), while the post-processing algorithms which were implemented at CMRE to analyse bio-optical and radiometric measurements performed simultaneously with the Lidar system and optical satellite data (i.e. from the Moderate Resolution Imaging Spectroradiometer, MODIS, and the Visible Infrared Imaging Radiometer Suite, VIIRS) are described in Section 3. The dataset retrieved from the available in situ water samples (Section 4) is successively used to investigate the ubiquity of optical linkages between the ocean and atmosphere at the global scale using data acquired during a Saharan dust phenomenon that occurred during the cruise. We analysed match-ups comparison between coincident (+/- 1hour) in situ and satellite retrievals, as well as historical satellite measurements to investigate the seasonal variability (Section 5). Results corroborate the hypothesis that the biasing of satellite chlorophyll-a retrievals are correlated with high deposited dust concentrations and may help climatologists to understand the impact of aerosols on correction for satellite ocean data, leading to better ocean colour products (e.g. atmospheric correction and ocean colour algorithms), especially in the presence of dust or other anthropogenic pollutants comparing.

Olives Noires 2016: experimental description and preliminary results Olives Noires 2016: experimental description and preliminary results

Date added: 03/23/2017
Date modified: 03/23/2017
Filesize: Unknown

Olives Noires 2016: experimental description and preliminary results. Dugelay, Samantha; Reardon, Eric; Furfaro, Thomas C.; Pailhas, Yan; Carreras, Marc. CMRE-MR-2017-001. February 2017.

This document provides an overview of the Olives Noires Mine Countermeasures Experiment 2016 (ONMEX'16) sea trial held from 15 to 28 September 2016 (including transit), in the Bay of Hyères, France. This trial was in support of the Autonomous Naval Mine Countermeasures (ANMCM) Programme. It describes the operational environment, the experiments conducted as well as the data collected.

Overall, ONMEX'16 was a very successful sea trial. The key achievements were:

- Deployment of the MUSCLE system in a blind Percentage Clearance trial (PC Trial) and overall high performance of the autonomy engine and good detection and classification rates.

- Extensive data collection to support the CMRE Autonomous Mine Search project for:

 - Automatic target recognition

- Advanced autonomy concepts on-board MUSCLE

- Advanced autonomy concepts on-board REMUS 100

- In situ planning and evaluation

- International collaboration: University of Girona (ESP), Heriot-Watt University (GBR).

 

A look into current standardisation gaps in underwater networks A look into current standardisation gaps in underwater networks

Date added: 03/14/2017
Date modified: 03/14/2017
Filesize: Unknown

A look into current standardisation gaps in underwater networks. Alves, João; Pelekanalis, Konstantinos; Petroccia, Roberto. CMRE-MR-2016-016. December 2016.

This report highlights some of the key missing elements preventing underwater communications interoperability. The requirement for interoperability and standards is motivated by NATO's multi-national nature where commonalities and joint operations should be explored when possible. To establish interoperable underwater networks, a myriad of challenges must be tackled. These start on establishing common channel models and metrics, continuing all the way into defining standardised networking protocols and security policies. JANUS is introduced as an example of a standardisation effort. This document proposes extensions to the current specification looking at future revisions of the standard.

Multitarget tracking using passive acoustic arrays Multitarget tracking using passive acoustic arrays

Date added: 02/07/2017
Date modified: 02/07/2017
Filesize: Unknown

Multitarget tracking using passive acoustic arrays. Meyer, Florian; Tesei, Alessandra. CMRE-MR-2016-020. December 2016.

This report addresses the problem of localising and tracking an unknown number of targets with unknown acoustic transmit signals from Time-Difference Of Arrival (TDOA) measurements acquired by hydrophone pairs. Based on the framework of random finite sets and finite set statistics, we formulate a Bayesian estimation problem and develop a particle-based detection, localisation, and tracking algorithm that is an extension and adaptation of the Track-Oriented marginal Multi- Bernoulli/Poisson (TOMB/P) filter [1, 2]. The proposed method overcomes the challenges related to the highly non-linear TDOA measurement model, the data association uncertainty, and the uncertainty in the number of targets to be localised and tracked. We evaluate the proposed method by means of simulations and by using measurement data acquired during an experiment performed within the PERSEUS project, where a compact hydrophone array was used as a payload on a covert long-endurance Autonomous Vehicles (AV). Our numerical results confirm that the algorithm is able to determine the number of targets correctly and that it can provide accurate location estimates for static and dynamic targets and in 2D and 3D scenarios when the number of clutter measurements is moderate and the probability of detection is high. In a 2D tracking scenario, where the PERSEUS array is under water and the targets are surface vessels, the localisation accuracy in range, i.e., distance from the array, critically depends on the array depth and the distance of the target. In the fully 3D scenario, at least two PERSEUS arrays are needed for accurate target localisation. These limitations are due both to physical constrains such as the limited bandwidth of the acoustic signals and the compact size of the array and are not related to the proposed algorithm.

User Login