The Full Picture

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Operation and data policy
The operation of CBERS satellites is shared between Brazil
and China according to a handover schedule. All special
requests and agreements for direct reception in third
countries are managed and negotiated by both sides. The
data distribution policy adopted for CBERS Program has
followed a pattern of enlarging the distribution while less-
ening the costs. In Brazil and China, the full resolution
data are delivered free through the Internet. Third parties
interested in receiving direct downlink CBERS data are
encouraged to assume the same free data policy.
The application of this data policy in Brazil and in
China resulted in an enormous increment of new users
and new applications. In Brazil, for example, INPE
(National Institute for Space Research) – the institution
that collects, processes and distributes CBERS data –
delivers regularly more than 300 scenes a week since the
application of this data policy. Up to now, more than
350,000 CBERS-2 scenes have been delivered around the
country. Seeking to improve the remote sensing in South
America, and as part of this free distribution policy, Brazil
has adopted the same policy for its neighboring coun-
tries. Because of this Brazilian policy, South America
countries are regularly using CBERS-2 data for their
remote sensing development and surveying policies.
In Brazil, governmental, private, NGO, educational
organizations related to agriculture, environmental
surveying, forest, law enforcement, are users of CBERS
data. The free data policy has changed the way people
work with remote sensing. New and better-trained profes-
sionals have been introduced to the remote sensing
services market, as they are exposed to the satellite prod-
ucts in a routine basis in their schools and offices.
Government organizations and NGOs can now use up-
to-date CBERS data in their surveying and mapping
projects and tasks. We believe part of the recent devel-
opment of the remote sensing field in Brazil can be
credited to the CBERS-2 data and to this data policy. In the
last Brazilian Remote Sensing Symposium (April 2007,
), more than 100 papers
were related to CBERS applications and developments.
The CBERS Program is a series of satellites that will be
present in the remote sensing arena at least for the next
10 years. Discussions on CBERS-5 and 6 have started
inside the Joint Program Committee with delegates from
China and Brazil. Thus, this Program has an important
role to play in the global watching initiatives from now
on. It has proved to be indispensable in Brazil and in
South America countries, and in China. And we expect
CBERS to play an important role to the world repre-
senting a key initiative from Brazil and China for
GEOSS, to the benefit of humankind.
China and Brazil are developing with South Africa,
Spain and Italy a framework for direct downlink of
CBERS-2B imagery. The satellite owners grant a free
access to the satellite and the ground stations owned by
the participant countries distribute the images to all
countries inside their footprints at no cost, using the EO
portal and GEONETCast when required.
the Chinese or Brazilian ground receiving stations. The onboard
recording abilities will be improved for CBERS-2B and CBERS-3 and
4 to increase its global capacity.
Payloads
Besides imaging sensors the payload for CBERS carry a transponder
that is a Data Collecting System, DCS, collecting data from ground-
based platforms (such as automatic weather and river gauging
stations, for example). The DCS is helpful to collect data in remote
regions such as the rain forest, mountains and lakes.
The imaging payloads are optical cameras, working from the blue
to the thermal infrared spectral regions. The cameras complement
each other and provide a useful range of spatial, spectral and tempo-
ral resolutions. The payload for CBERS-1 and 2 are similar; for
CBERS-2B there are two important changes in one of the cameras
and in the recording technology. As for CBERS-3 and 4 all the
cameras will change, and there will be new capabilities.
The main camera of CBERS-1, 2 and 2B is the CCD (High
Resolution Imaging Camera), with a swath of 113 km, 20 m GIFOV
(Ground Instantaneous Field of View), 8 bits quantization, and ±32o
cross-track pointing ability. The nominal revisit time is 26 days;
however, with the off-nadir pointing ability, the revisit interval can
be less than five days. The spectral coverage of this camera is from
blue to near-infrared in four bands, plus a panchromatic band.
The second camera is the WFI (Wide Field Imager) – a CCD
device with a swath of 890 km, 260 m GIFOV, 8 bits quantization,
and two spectral bands: red and near-infrared. With this large swath,
its revisit is close to five days. This advantage makes it suitable for
early warning and disaster assessment.
The third camera is the IRMSS (Infrared Multispectral Scanner).
While the first two cameras are pushbroom-based technology, this is
a whiskbroom imager. It has four channels: two in the shortwave
infrared band and a panchromatic (visible and near-infrared) band
with 80 m GFOV, and a thermal band with 160 m GIFOV. The swath
is 120 km, and the revisit time is 26 days.
For CBERS-2B the IRMSS is replaced by a High Resolution
Panchromatic Camera (HRC), with 2.7 m GIFOV and a 27 km swath.
Since the satellite imaging track pattern is designed for CCD, a
special mode was designed for CBERS-2B to house the HRC small
swath while getting the best benefits from this HRC camera. Another
important change for CBERS-2B is the improvement of its onboard
recording capacity, based on solid-state technology, more reliable and
with higher recording capability.
CBERS-3 and 4 will become the new generation of the CBERS
family in the next five years. These satellites, while keeping the
same orbital characteristics, were designed to house four imaging
payloads. The CCD will be upheld as the main camera, and its char-
acteristics will not change much from the previous satellites. A
second camera is similar to the CCD in spectral coverage, but with
10 m GIFOV, and a panchromatic band performing in 5 m GIFOV.
This camera has steering mirror ability, and a swath of 60 km swath.
The IRMSS will be back, but with the spatial resolution improved
to 40 m for the SWIR and panchromatic bands, and to 80 m for the
thermal band. Finally, the payload will also incorporate an
Advanced Large Field Imager (AWFI) with the same spectral bands
as the CCD camera, but its GIFOV will be improved to 73 m (from
260 m on CBERS 1 and 2), for a swath of 866 km. This new gener-
ation of CBERS 3 and 4 will significantly improve the imaging
capacities and the quality of images from the previous ones.
GEOSS C OMPONENTS – D ISSEMINATION/INFORMATION S YSTEMS