RADARSAT-2 mode selection for maritime surveillance Roger De Abreu, Matt Arkett, Angela Cheng, Tom Zagon, Paris W. Vachon and John Wolfe This publication is protected by copyright. Defence R&D Canada warrants that the work was performed in a professional manner conforming to generally accepted practices for scientific research and development. This report is not a statement of endorsement by the Department of National Defence or the Government of Canada. Defence R&D Canada – Ottawa External Client Report DRDC Ottawa ECR 2011-168 November 2011 RADARSAT-2 mode selection for maritime surveillance Roger De Abreu, Matt Arkett, Angela Cheng, Tom Zagon, Derek Mueller Canadian Ice Service, Environment Canada Paris W. Vachon, John Wolfe DRDC Ottawa Prepared For: Canadian Space Agency John H. Chapman Space Centre 6767 Route de l'Aéroport Saint-Hubert, Quebec J3Y 8Y9 This publication is protected by copyright. Defence R&D Canada warrants that the work was performed in a professional manner conforming to generally accepted practices for scientific research and development. This report is not a statement of endorsement by the Department of National Defence or the Government of Canada. Defence R&D Canada – Ottawa External Client Report DRDC Ottawa ECR 2011-168 November 2011 Principal Author Original signed by Paris W. Vachon Paris W. Vachon Defence Scientist Approved by Original signed by Caroline Wilcox Caroline Wilcox Head, Radar Applications and Space Technologies Section Approved for release by Original signed by Chris McMillan Chris McMillan Chair, Defence R&D Canada – Ottawa Document Review Panel This report is the final project deliverable to the Canadian Space Agency under the Government Related Initiatives Program project "RADARSAT-2 Mode Selection for Maritime Surveillance". © Her Majesty the Queen in Right of Canada, as represented by the Minister of National Defence, 2011 © Sa Majesté la Reine (en droit du Canada), telle que représentée par le ministre de la Défense nationale, 2011 Abstract …….. The main objective of the RADARSAT-2 Mode Selection for Maritime Surveillance (R2MS2) project was to identify and recommend ScanSAR-based maritime surveillance modes for RADARSAT-2 (R-2), while also preparing for exploitation of the RADARSAT Constellation Mission (RCM). The primary focus of R2MS2 was on the performance of wide swath, ScanSAR modes of operation including ScanSAR Wide (SCW) and ScanSAR Narrow (SCN). The following maritime surveillance applications were considered: sea ice surveillance; ice island monitoring; iceberg detection; ship detection; wind speed estimation; oil spill detection; and ocean feature detection. Furthermore, several image quality issues were considered: application look-up table (LUT) performance in converting floating point numbers in the processor into integers in the image product; the block adaptive quantization (BAQ) setting for reduction of raw data volume; and noise subtraction for mitigation of the visual impact of the noise floor for low signal to noise ratio acquisitions. Finally, several tools were developed for DRDC Ottawa’s Image Analyst Pro (IA Pro) software test bed to support R2MS2 data processing needs. For the maritime surveillance applications considered, the approach included a combination of theoretical analysis and field trials to gather new data sets of known targets, with validation whenever possible. The trials often focused on the collection of R-2 Fine Quad (FQ) mode imagery such that all linear polarization choices (i.e., HH, HV, VV, and VH) were simultaneously available. Then, observations could be extended to the ScanSAR cases through appropriate modification of the noise floor, spatial resolution, and radiometric resolution. Along with recommended surveillance modes by application, multiple use (i.e., one acquisition serving multiple maritime applications) opportunities were identified that would streamline order planning and maximize R- 2 utilization. DRDC Ottawa ECR 2011-168 i Résumé …..... Le principal objectif du projet de sélection de modes RADARSAT-2 adaptés à la surveillance maritime (R2MS2) était d’identifier et de recommander des modes de surveillance maritime ScanSAR pour RADARSAT-2 (R-2), tout en préparant l’exploitation de la mission de la constellation RADARSAT (MCR). Le projet R2MS2 a mis l’accent principalement sur la performance des modes de fonctionnement ScanSAR à large bande, y compris le mode ScanSAR large (SCW) et le mode ScanSAR étroit (SCN). Voici les applications de surveillance maritime qui ont été examinées : surveillance des glaces de mer; surveillance des îles de glace; détection des icebergs; détection des navires; estimation de la vitesse du vent; détection de déversements d’hydrocarbures et détection des caractéristiques des océans. On a aussi tenu compte de plusieurs questions liées à la qualité des images : performance de la table de consultation (LUT) des applications dans la conversion des nombres à point flottant du processeur en nombres entiers dans les produits d’image; le réglage de la quantification adaptative des blocs (BAQ) en vue d’une réduction du volume de données brutes et de la soustraction du bruit en vue de l’atténuation de l’incidence visuelle du plancher de bruit pour les acquisitions du rapport signal/bruit. Enfin, plusieurs outils ont été mis au point pour le banc d’essai du logiciel Image Analyst Pro (IA Pro) de RDDC Ottawa à l’appui des besoins en traitement de données du projet R2MS2. Pour les applications de surveillance maritime examinées, l’approche a compris une combinaison d’analyses théoriques et d’essais sur le terrain en vue de la collecte de nouveaux jeux de données de cibles connues, moyennant validation dans la mesure du possible. Les essais ont souvent porté sur la collecte d’images en mode fin à quadruple polarisation (FQ) R-2, de sorte que tous les choix de polarisation rectiligne (c’est-à-dire HH, HV, VV et VH) étaient disponibles simultanément. Il était alors possible d’élargir les observations aux cas ScanSAR par la modification appropriée du plancher de bruit, la résolution spatiale et la résolution radiométrique. Outre les modes de surveillance recommandés par application, on a repéré des possibilités d’utilisation multiple (c’est-à-dire une acquisition pouvant servir dans le cas de plusieurs applications maritimes) qui permettraient de rationaliser la planification de l’ordonnancement et d’optimiser l’utilisation de R-2. ii DRDC Ottawa ECR 2011-168 Executive summary RADARSAT-2 mode selection for maritime surveillance Roger De Abreu; Matt Arkett; Angela Cheng; Tom Zagon; Derek Mueller; Paris W. Vachon; John Wolfe; DRDC Ottawa ECR 2011-168; Defence R&D Canada – Ottawa; November 2011. Introduction: The RADARSAT-2 Mode Selection for Maritime Surveillance (R2MS2) project was established in 2008 as a collaborative R&D activity between the Canadian Ice Service (CIS) and Defence R&D Canada – Ottawa (DRDC Ottawa). With funding in part from the Canadian Space Agency (CSA) via their Government Related Initiatives Program (GRIP), the main objective of the R2MS2 project was to identify and recommend ScanSAR-based maritime surveillance modes for RADARSAT-2 (R-2), while also preparing for exploitation of the RADARSAT Constellation Mission (RCM). The key idea was to examine dual use (i.e., one acquisition serving multiple maritime applications) opportunities that would streamline order planning and maximize R-2 utilization. Maritime surveillance requirements often compete from a SAR perspective, with certain applications focussing on the ocean clutter, while other applications require suppression of the ocean clutter. The focus of R2MS2 was on the performance of wide swath, i.e., ScanSAR modes of operation including ScanSAR Wide (SCW) and ScanSAR Narrow (SCN). ScanSAR maximizes the area coverage rate, a key requirement for maritime surveillance. The following maritime surveillance applications were considered: sea ice monitoring; ice island monitoring; iceberg detection; ship detection; wind speed estimation; oil spill detection; and ocean feature detection. Furthermore, the following image quality issues were considered: application look-up table (LUT) performance in converting floating point numbers in the processor into integers in the image product; and the block adaptive quantization (BAQ) setting for reduction of raw data volume. Finally, several tools were developed for DRDC Ottawa’s Image Analyst Pro (IA Pro) software test bed to support R2MS2 data processing needs and other SAR users. For the maritime surveillance applications considered, the approach included a combination of theoretical analysis and field trials to gather new data sets of known targets, with validation whenever possible. The trials often focused on the collection of R-2 Fine Quad (FQ) mode imagery such that all linear polarization choices (i.e., HH, HV, VV, and VH) were simultaneously available. Then, observations could be extended to the ScanSAR cases through appropriate modification of the noise floor, spatial resolution, and radiometric resolution. Results: Sea ice monitoring – There exists a mature operational capability to chart sea ice type (e.g., first year ice, multiyear ice, open water) based primarily upon radar backscatter and image texture. An extensive database of R-2 SCW dual-polarization images of sea ice was acquired and backscatter signatures as a function of ice type were collected. It was shown that use of cross polarization can dramatically improve the estimation of ice concentration and ice type separability