Low Earth-orbit satellites enable defence analysts to have good, current coverage of areas of interest. Jonathan Shears details a new geointelligence product that will take advantage of the improved capabilities of both SPOT 6 and SPOT 7 satellites
Military commanders typically operate in high tempo environments and feed off a variety of intelligence sources to reach their decisions. Good intelligence leads to better situational understanding and hence improved knowledge, which will ultimately underpin optimum decision-making. Accordingly, geointelligence (‘geoint’) products need to efficiently and effectively create an environment in which all intelligence sources can be fused and combined to provide visualisations and easy access to attribute information.
A geo-referenced foundation layer is therefore now a key component for all geoint activities. To operate as a geoint tool, foundation layers must have high absolute horizontal accuracy and be as current as possible.
Traditionally, cartographic mapping acted as the foundation layer. Advancements in mapping brought about by satellite imagery didn’t affect this, because there was a mutually exclusive dichotomy of coverage over currency.
However, low Earth orbit imaging satellites are now capable of almost blanket global coverage in days and weeks, with very high relative positional accuracy. Their autonomous operation and independence of ground survey or local presence mean satellites can obtain intelligence information for any geographical region, regardless of hazard, hostility or inaccessibility political or physical. For military applications, denied areas are equally as accessible as undenied areas.
As a result, the heyday of cartographic mapping has long since passed and constellations of satellites have become the primary data sources for reference mapping.
The importance of sharing
Clearly, to support multi-agency and coalition-based operations, geoint databases must be easily sharable, not only through ‘horizontal’ peer-to-peer distribution, but also ‘vertical’ distribution, so that the exchange and synchronisation of geospatial data between all echelons can be achieved.
Astrium Services’ new Foundation Layer product has been specifically developed to support the high currency and coverage rate requirements of the geoint community. This dataset comprises seamless orthorectified, colour imagery mosaics covering thousands of square kilometres, underlying digital elevation models (DEMs) and very high resolution imagery inserts over specific areas of military interest, such as cities, airfields, ports and harbours.
It takes advantage of the high combined re-visit, high accuracy and high coverage rates of the only multi-resolution imaging satellite constellation currently in operation. This constellation is capable of collecting upwards of 20m km² of data every day, at resolutions from 50cm to 2.5m for any point on Earth. Wide area swath widths of up to 60km x 60km for any region ensure the necessary rapid initial creation and enduring currency required by geoinit. The constellation is also able to acquire imagery at night and regardless of the weather, meaning Astrium Services can guarantee delivery.
Get a synoptic view
GEOMaps are seamless, orthorectified, contiguous, countrywide mosaics derived from satellite imagery. Initial delivery of GEOMaps is based on recent SPOTMaps archive products, which provide nationwide orthorectified coverage derived from SPOT 5 colour images at a resolution of 2.5m over high interest, politically unstable and potentially volatile countries.
Mosaics, updated every two years, will be created using SPOT 6 and soon SPOT 7, data so will offer the same coverage but at a resolution of 1.5m.
For emergency situations, the update frequency can be increased to 12 months due to the wide coverage capacity of SPOT 6 and SPOT 7 (3,600km² per scene), and the GEOMaps will be updated in less than one year.
Mosaicked data fused from multi-resolution optical – and even synthetic aperture radar (SAR) – sensors gives a synoptic picture, as well as providing the local level of detail and precision needed for more in-depth analysis in visualising an entire territory with similar currency throughout, providing a foundation to visualise and share multi-layer intelligence and reliably sharing information on a common geographic framework region.
Reach the right height
Accurate DEM layers are vital for building very high-quality elevation databases and ensure perfect registration of data layers for exploitation in GIS systems.
SPOT DEM Precision is designed to a very demanding specification, assuring uniform geometric quality and guaranteeing DTED2 performance. Designed to meet military requirements, SPOT DEM Precision gives quality and traceability indicators for each pixel:
- Absolute horizontal and vertical accuracy.
- Source data.
- Production processes.
- All corrections and checks.
The DEM Precision product is uniquely based on the global Reference 3D, which was created to support guided-missile programmes. Derived from data from both optical and SAR satellite sensor technologies, it allows for the first time maximum worldwide coverage independent of terrain characteristics and weather conditions.
This makes SPOT DEM Precision an excellent tool for building on-board databases for UAVs, missiles and aircraft, and for mission planning, well suited to defence ministries and weapons manufacturers.
Reveal the details with Pléiades
Whilst broad area coverage serves battlefield-scale planning activities, such as logistics, ORBATS and tactical communications, higher resolution is often required for more intelligence-based activities over specific target sites.
Astrium Services meets this requirement using its dual Pléiades 1A and 1B 50cm products. These provide fresh and accurate VHR products over particular locations, and can be used for comparison with existing maps (for example, for change detection) or detection of high-activity areas and infrastructural detail target sites, such as harbours, airfields and cities.
In many countries with geopolitical instability, military and critical infrastructures are rapidly changing and as a result, geoint analysis is required at highly regular rate of update. Data maintenance is key to ensuring the continued integrity and intelligence value of a mapping database.
With this in mind, the Astrium Services’ maintenance service is designed to ensure intelligence analysts are using the most recent data and to guarantee that the accuracy of any derived analysis outputs is not compromised. To prevent tis databases from becoming obsolete, Astrium Services proposes to undertake data updates using the latest available satellite acquisition.
Therefore, countrywide mosaics will be updated every two years, and could be refreshed yearly in case of critical situations in a country. Areas prone to higher changing rates, such as cities, ports, harbours or airfields, require more frequent updates, so will be renewed every year.
A geo-referenced foundation layer is now a key component for all geoint activities
Jonathan Shears is principal geospatial consultant – defence and security at Astrium Services (www.astrium-geo.com)