After moon mission, ISRO to launch a breakthrough satellite

Bangalore, Feb 17 (PTI) After its successful unmanned
moon mission Chandrayaan-I, Indian Space Research Organisation
is poised to launch a "breakthrough" remote sensing satellite
RISAT that can take pictures of earth during night and even
see through clouds and fog.

Bangalore-headquartered ISRO is targeting a March last
week date for launching the 1,780-kg Radar Imaging Satellite
(RISAT) along with ANUSAT, a 35-kg micro-satellite designed by
Chennai-based Anna University, on board the indigenously built
Polar Satellite Launch Vehicle (PSLV) from Sriharikota.

The remote sensing satellites launched previously by
ISRO cannot carry out the operations of the type which can be
undertaken by RISAT.

Indian space scientists see RISAT as a major milestone
for the country as far as remote sensing satellites are
concerned. RISAT mission would have a C-band Synthetic
Aperture Radar (SAR) payload, operating in a
multi-polarisation and multi-resolution mode.

"So far, all satellites launched by ISRO are optical
remote sensing satellites. But RISAT will have all other
capabilities," ISRO spokesperson S Satish told PTI.

"This will be a major breakthrough as far as remote
sensing projects are concerned, especially during cloudy
season or during flood season...this will be of great
advantage", Satish said. "It can see through the clouds".

Satish said ANUSAT will give a first-hand exposure to
students in the university towards building a satellite.

SAR, being an active sensor, operating in the microwave
range of electromagnetic spectrum, provides the target
parameters such as dielectric constant, roughness, and
geometry, and has the unique capability for day-night imaging,
and imaging in all weather conditions including fog and haze,
and also provide information on soil moisture.

SAR payload is based on an active phased array
technology using transmit/receive modules, which would provide
necessary electronic agility for achieving the multi-mode
capability, providing spatial resolutions of three metres to
50 metres, and ten kms to 240 kms swath modes to cater to
different applications.

ANUSAT mission's main objective is to involve
universities in building micro satellites as a means to
promote and encourage intra-disciplinary technologies with
ISRO's help.

ANUSAT carries a digital store and forward payload for
amateur communication. In addition, a number of technological
payloads such as digital receiver and turbo coder, MEMS-based
gyro and magnetic field sensor are planned to be flown on
board. Structure, solar panels, chemical battery, sensors and
actuators had been supplied by ISRO while payloads and other
satellite subsystems were designed and fabricated at Anna
University. PTI RS
SAK