Unequal Friendship and SAR Technology

Tapan Misra

Russel Keith Raney

Russel Keith Raney and myself share an unequal friendship. He was in Master’s, when I was born, in another distant continent, in another country, trying to rise like Sphinx from the injuries inflicted for centuries of domination by invaders and colonial masters.

What draws us together is a common trait – being maverick. In 1978, NASA launched first SAR satellite in space, Seasat. NASA employed analogue data recording and optical processing, developed by JPL. NASA scientists believed that, SAR processing was so complex that no computer, at that timeframe, could process SAR data. Everybody in NASA gave a cold shoulder to this gentleman, who proposed that digital SAR processing is more elegant and doable by adding a few hardware tricks. He was disheartened and left for Canada, developed the first digital SAR processor and brought SAR processing to adolescence. Rest is history.

The celebrated Canadian SAR satellite Radarsat had imprints of his clever system design and leadership. He discovered the very elegant Chirp Scaling algorithm for SAR processing. Mini SAR from NASA on-board our own Chandrayan-1 was his brain child.

MiniSAR made history as it conclusively proved that water is present as dirty ice in the dark depths of polar craters, raising the hope of establishing the first human base, outside our blue planet.

I was drawn to him in the EuSAR Dresden conference in 2006 where he proposed a maverick idea of Hybrid polarimetry. Everybody listened to him while yawning and with lack of interest. But I sensed a great idea and implemented hybrid polarimetry for the first time in RISAT-1. I was undaunted by severe opposition in ISRO trying to implement an idea which nobody had implemented! RISAT turned SAR polarimetry upside down and democratised the polarimetry science. Today it is the global standard for all spaceborne SAR satellites conceived after RISAT-1.

I was pleasantly surprised when I received his heartfelt wishes for our new startup SISIR Radar. He even decided my designation which I am going to obey. The blessing from Guru to Shishya (teacher to pupil), which we are going to cherish forever.

Click for further Reading


Tapan Misra

Tapan Misra is a distinguished scientist, who has earlier served as Director Space Application Centre and has contributed immensely to India’s Space Programme. He has now founded a startup to make synthetic aperture radars (SAR). His company SISIR Radar will make synthetic aperture radars that can can be fitted on drones to take clear pictures even at low altitude.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.