India to launch Israel-backed satellite

[Screaming Skull]

The Indian RISAT-2 looks mighty similar to Israel's TecSAR. There are rumors that the Indian RISAT-2 is an off the shelf Israeli TecSAR. Though ISRO is tight lipped about the specs of RISAT-2, if the rumors are true then RISAT-2 is going to be one hell of a killer of a spy sat.
---(Purely my opinions. I may be wrong though!)

Here are the specs of the Israeli TecSAR.

TecSAR

The Mini class, low earth orbit TecSAR, is offered as an off-the-shelf product by Israeli Aerospace Industries (IAI) and ranks among the world's most advanced space systems.

Its Synthetic Aperture Radar (SAR) uses a large dish-like antenna to transmit and receive radar signals that can penetrate darkness and thick clouds providing images with 1m resolution.

The Multi mode SAR is capable of high resolution imaging of Spot (1m), Strip (3m), Mosaic(1.8m) and Wide coverage (8m).

The highly agile bus design in combination with the body-pointing parabolic antenna dish system permits greatly increased viewing capabilities from the spacecraft. The spacecraft/antenna system may be dynamically redirected into any direction of the flight path (i.e. in the cross-track as well as in the along-track direction). Thus, a wide FOR (Field of Regard) within the incidence-angle range may be obtained on either side of the ground track for event monitoring coverage.

Strip mode: the synthetic apertures are targeted on wide geographical swaths. The spacecraft performs synchronous imaging and does not change its orientation during observations except for some small maneuver due to the need to keep the imaging strip parallel to the ground track. Squinted strip imaging is possible.

Wide coverage ScanSAR: The coverage of large strips is achieved by electronic beam steering. Three beams are used in the nominal wide coverage mode which create three footprints (subswaths) in the target area. The ground resolution in this mode is decreasing since the integration time is split up among the subswaths. The swath width can be increased by using more antenna beams. In principle the swath width may get to more than 100 km for some incidence angles. However, this reduces the ground resolution to about 20 m.

Spotlight mode: This focuses on a specific, pre-assigned target. In spotlight, the spacecraft performs mechanical steering to halt the antenna footprint in a specific target area. The longer integration time over the spot target area yields an improved azimuth resolution. The range resolution is achieved in adjusting the bandwidth to the incidence angle. The TecSAR ability for spotlight imaging in squint allows for multi-look imaging without any loss in resolution. To obtain a multi-look image of a given target area, a number of spotlight images are being observed, each at a different squint angle.

Mosaic mode: The radar imager slews its focus on a number of spots in the same general target area. The mosaic mode enables to extend the limited coverage of the spot mode by using the electronic steering capability of XSAR. In mosaic mode the radar beam scans in the range direction while the mechanical maneuvering advances the strip line in the azimuth direction. Hence, this mode may also be interpreted as the spot version of ScanSAR.



Artist's rendition of the TecSAR spacecraft in Earth orbit. Photo Credit: IAI



Illustration of the TecSAR spacecraft. Photo Credit: IAI Systems Ltd.



Multi modes of SAR. Photo Credit: ELTA Systems Ltd.



Illustration of the wide coverage mode. Photo Credit: ELTA Systems Ltd.



Illustration of the mechanical and electrical beam steering in the mosaic mode. Photo Credit: ELTA Systems Ltd.

 

[shravan]

India already has a satellite which has a resolution of 1m, so why so much hype now?? And also what's the need to give so much advertisement to a spy satellite??

US, Europe, Canada and Israel are among the few countries that have the SAR capability.

 

[Screaming Skull]

India already has a satellite which has a resolution of 1m, so why so much hype now?? And also what's the need to give so much advertisement to a spy satellite??

'resolution of 1m' in perfect weather conditions and during day time only. RISAT-2 will have a resolution of about 10-12cm in all weather conditions during day and night amidst thick cloud cover etc.

The SAR tech. is quite advanced. Even China doesn't possess this capability.

 

[PeacefulIndian]

'resolution of 1m' in perfect weather conditions and during day time only. RISAT-2 will have a resolution of about 10-12cm in all weather conditions during day and night amidst thick cloud cover etc.

The SAR tech. is quite advanced. Even China doesn't possess this capability.

So have we contributed something to the technological development? Or is it just a straight forward purchase & launch?

 

[Screaming Skull]

So have we contributed something to the technological development? Or is it just a straight forward purchase & launch?

ISRO's very tight lipped bout it. Can't say what the exact contribution is. The heart of the sat that s the SAR is definitely Israel's. We might have integrated it with the remaining indigenous stuff.

Remember India has its own spy sat program called RISAT-1 that will have 100% indigenous parts including the SAR. Since, this program was delayed and Mumbai happened, GoI sought Israeli help.

Also I am guessing that ISRO s been getting pics from Israel's TecSar (However, I can't confirm this). There is news that ISRO was very impressed with TecSar when they launched it earlier using an Indian PSLV. It s the most advanced spy sat ever built!!!

 

[Screaming Skull]

Isro to launch high-end satellite on Monday​

17 Apr 2009,

CHENNAI: The Indian Space Research Organisation (Isro) will on Monday put in orbit its first radar imaging satellite (Risat), which can watch'
the earth under all-weather conditions, day and night.

Isro's workhorse PSLV (C-12) will take off at 6.45am from the Satish Dhawan Space Centre at Sriharikota, an island by the sea 100km north of Chennai. About 17 minutes later, the 300-kg Risat will be put in an orbit 550km from the earth. Riding piggyback on Risat will be a microsatellite called Anusat, developed by Anna University, Chennai.

"The countdown will start 48 hours before take-off (Saturday morning). As of now, everything is going on fine. Risat, which can penetrate clouds and observe earth under all climatic conditions, will be extremely useful in disaster management," Isro spokesperson S Satish told TOI. Unlike Isro's previous remote sensing satellites that used optical imaging, Risat uses synthetic aperture radar (SAR) that has several antennas to receive signals that will be processed into high-resolution pictures.

While its applications in mapping and managing natural disasters such as floods and landslides are spoken about, Risat will come in handy for defence applications as well. Isro had started work on a 1,780-kg Risat, but shelved its launch to advance the launch of the present 300-kg variant. Defence sources confide that the lighter Risat version was assembled on a war footing in the wake of terrorist attacks. "Risat has been put together with inputs from the Israeli Space Agency (ISA), but the satellite images will be used solely for Indian purposes," Satish said.

Also in the PSLV-C12 payload will be Anusat, the first satellite to be assembled by an Indian university. "Scores of students and faculty members from different streams have been working on Anusat for six years," said Anusat project director P V Ramakrishna. Anusat will be a store-and-forward communication satellite that will enable transfer of confidential academic material like exam question papers, to get rid of leakages (Brilliant).

PSLV-C11 had, on October 22, 2008, carried the lunar probe as part of Chandrayaan-I. Ever since it launched the first satellite Aryabhatta on April 1, 1975, Isro has launched more than a dozen satellites, including the INSAT (Indian National Satellites) series for communication, broadcasting and meteorology and IRS (Indian Remote Sensing Satellites) for resources monitoring and management.

 

[godsavetheworld]

Also in the PSLV-C12 payload will be Anusat, the first satellite to be assembled by an Indian university. "Scores of students and faculty members from different streams have been working on Anusat for six years," said Anusat project director P V Ramakrishna. Anusat will be a store-and-forward communication satellite that will enable transfer of confidential academic material like exam question papers, to get rid of leakages (Brilliant).

Now we have lost the even 0.0000000001% chance we had of a paper being leaked and hence being cancelled. What crap.

 

[satishkumarcsc]

Damn man...screw the ANUSAT. But anyways my Univ uses a far more effective way of dealing with paper leak.