The DigitalGlobe Constellation
DigitalGlobe owns and operates the most agile and sophisticated constellation of high-resolution commercial earth imaging satellites. QuickBird, WorldView-1 and WorldView-2 together are capable of collecting over 500 million km2 of quality imagery per year and offering intraday revisit around the globe.
There is no longer a question of whether timely imagery is available. If we don’t already have what you need in our vast ImageLibrary, we can get it faster than ever before. With the addition of our newest satellite, WorldView-2:
Our constellation features several technical advantages:
QuickBird is the first 60 cm commercial satellite. WorldView-1 and WorldView-2 are some of the most agile commercial satellites ever flown; WorldView-1 provides 50 cm panchromatic imagery and in-track stereo capabilities. WorldView-2 brings .46 cm** resolution, 8-band color imagery, and in-track color stereo capabilities around the world. Our aerial collection sets the standard with all new imagery at 1 ft. resolution or better.
Collection Capacity & Rapid Revisit
With the combination of QuickBird, WorldView-1 and WorldView-2, we are able to collect roughly 1.5 million kilometers of high-resolution imagery – 60 cm or better – every day. That’s the equivalent of three times the landmass of the earth every year. The DigitalGlobe constellation also has the largest high-resolution multispectral capacity, including 8-band imagery, an industry first.
With all three satellites working in concert, the DigitalGlobe constellation provides the most same-day passes of any commercial high-resolution constellation. It is capable of achieving intraday revisit across most of the globe, and at 1m GSD, it never exceeds two days.
Greater Agility and In-Track Stereo
WorldView-1 and WorldView-2 are the only two commercial satellites equipped with control moment gyroscopes (CMGs). This high-performance technology provides acceleration up to 10X that of other attitude control actuators and improves both maneuvering and targeting capability. With the CMGs, slew time is reduced from over 60 seconds to 12 seconds or less to cover 200 km. This means that both WorldView-1 and WorldView-2 can rapidly swing from one small target to another, or collect large image swaths over a single area. The agility provided by the CMGs also enables both WorldView-1 and WorldView-2 to efficiently collect in-track stereo images for the creation of highly detailed Data Elevation Models.
DigitalGlobe’s second generation satellites, WorldView-1 and WorldView-2 are equipped with advanced geopositional technology. These technological advancements are providing significant improvements in accuracy as well. The accuracy specification has been tightened to 6.5 m CE90 right off the satellite, meaning no processing, no elevation model and no ground control, and the measured accuracy is coming in at a remarkable 4.1 m CE90.***
Every satellite in the DigitalGlobe constellation is capable of collecting sub-meter imagery. QuickBird was the first commercial satellite able to collect 60 cm resolution, and it continues to deliver high-quality imagery. WorldView-1 has been collecting 50 cm panchromatic imagery since 2007, and WorldView-2 has been collecting 46 cm* resolution 8-band imagery since October of 2009.
The DigitalGlobe constellation has the largest high-resolution multispectral capacity of any commercial imagery provider. QuickBird has been reliably collecting 2.44 m, 4-band multispectral imagery since 2001, and WorldView-2 is the only commercial satellite capable of collecting 1.84 m* 8-band multispectral imagery. Along with the four typical VNIR bands: Blue (450-510), Green (510-580), Red (630-690) and Near-IR (770-895), WorldView-2 is introducing the following new color bands for enhanced multispectral analysis:
Coastal Band (400 - 450 nm):
This band supports vegetation identification and analysis, and supports bathymetric studies based upon its chlorophyll and water penetration characteristics. Also, this band is subject to atmospheric scattering and will be used to investigate atmospheric correction techniques.
Yellow Band (585 - 625 nm):
Used to identify "yellowness" characteristics of targets, important for vegetation applications. Also, this band assists in the development of "true-color" hue correction for human vision representation.
Red Edge Band (705 - 745 nm):
Aids in the analysis of vegetative condition. Directly related to plant health revealed through chlorophyll production.
Near Infrared 2 Band (860 - 1040 nm):
This band overlaps the NIR1 band but is less affected by atmospheric influence. It supports vegetation analysis and biomass studies.
Pour de plus amples informations, contactez-nous.
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|Mise à jour le Vendredi, 29 Octobre 2010 14:58|