The CBERS satellite has a set of sensors or instruments - WFI (Wide Field Imaging Camera), CCD (Imaging High Resolution Camera), IRMSS (Infrared Multispectral Scanner) and HRC (High Resolution Panchromatic Camera) with a high potential for satisfy multiple application demands.
The application potential of a given sensor is established as a function of its spatial resolution, temporal resolution, and spectral and radiometric characteristics. In order to maximize the results to improve the cost/benefit ratio one should consider the trade-off between the application needs and the sensors characteristics. Following are indicated some applications for each camera although the possibility of applications is very ample.
The High Resolution Imaging Camera (CCD)
, with its good spatial resolution – 20 meters – in four spectral bands plus one panchromatic band, is suited for observation of phenomena and objects whose details are important. As it has a field of view of 120Km, it is suited for city and region studies. Given its temporal frequency of 26 days, it supports the analysis of phenomena whose duration is compatible with its temporal resolution. This temporal resolution can be improved as the CCD has the capacity of side view. Its bands are located in the spectral zone of the visible and near infrared, which allow good contrast between vegetation and other type of objects.
Here follows some potential CCD applications to be pointed out:
- Vegetation: identification of forest areas, forest alterations in parks, forest reservations, native or man-made forests, area quantification, recent fire scars.
- Agriculture: identification of agricultural fields, area quantification, monitoring of agricultural development and expansion, quantification of central pivots, support for crop forecasting, various inspections.
- Environment: identification of anthropic anomalies across water channels, reservoirs, forests, urban surroundings, roads; analysis of natural recurrent events, compatible with camera resolution, mapping of use of land, urban sprawling.
- Water: Identification of water-continent borders, coast studies and management, reservoir monitoring.
- Cartography: as this camera has sideways pointing of 32º east and west, in few steps, it enables the acquisition of stereoscopic images for a proper cartographic analysis. This feature also makes possible the acquisition of images of a certain area in a terrain in shorter intervals, which is useful for the monitoring of dynamical phenomena.
- Geology and soil: support for soil survey and geology.
- Education: generation of support material for educational activities in geography, environment and other subjects.
The IRMSS (Infrared Multispectral Scanner)
, present in CBERS-1 and -2, camera has two spectral bands in the medium infrared region and a panchromatic band with a 80 meters spatial resolution, plus one band in the thermal infrared region with 160 meters. Its applications are the same as those of the CCD camera with proper adaptations. Additional applications are:
- Analysis of phenomena that present surface temperature modifications.
- Generation of state region mosaics.
- Generation of image charts.
The WFI (Wide Field Imager)
is able to image large territorial extensions, 890km wide. This characteristics makes WFI very interesting for observing phenomena whose magnitude or interest lie in the macro-regional or state scale. As a function of this wide spatial coverage, its temporal resolution has a gain – it can generate images of a certain region with a less than five days interval. Here follow some of its applications:
- Generation of state region and national mosaics.
- Generation of vegetation indexes for monitoring purposes.
- Monitoring of dynamical phenomena like agricultural harvests, persistent fires.
- Alert system, where a WFI image can serve as an indication for the acquisition of higher resolution images of the CCD or IRMSS cameras.
- Joint operation with other world data collecting systems of low to medium resolution.
The HRC (High-Resolution Panchromatic Camera)
is apt to image a relatively narrow strip - 27km- and with extremely high resolution, of 2.7m pixel dimension. The operation mode is based on a 130 days revisit. In this fashion it will be possible to obtain at least two complete coverages of the country. This camera will not be able to provide stereoscopy. Among its applications, one may mention the following:
- Detailed national or state mosaics.
- Actualization of thematic maps and other.
- Product generation for local or county planning.
- Urban and intelligence applications.
Image Credits: CBERS/INPE.