The NIHoF honours "people responsible for the greatest technological advances that make human, social and economic progress possible."
Mitra, an alumnus of Presidency College, Kolkata, and Calcutta University, was honoured for inventing the first dental filling material to include nanoparticles. "The new composite filling material, called Filtek Supreme Universal Restorative, is a versatile material that could be used for restoring teeth in any area of the mouth; mimicked the beauty of natural teeth; had better polish retention; and exhibited superior strength than existing dental composites," the release from NIHoF said.
The product line has been used in more than 600 million dental restorations worldwide, according to 3M, the American conglomerate that Mitra worked for 32 years before retiring in 2010 to start an R&D consulting company with her husband. Mitra, 69, was a chemist at 3M Oral Care, the dental products division of 3M, best known for its Post-it notes and Scotchgard fabric protector. Her inventions have led to a number of breakthrough dental technologies, including nanocomposites and dental adhesives.
Paulraj, professor emeritus at Stanford, has been recognized for his 1992 US patent on MIMO - Multiple In-Multiple Out - wireless technology. This uses multiple antennas both at the transmitter and receiver in a wireless link to boost wireless data rates. The ubiquitous broadband wireless internet access we enjoy today - and 5G in the near future - would not be possible without MIMO technology. It has become the basis of all current and future wireless networks, making it the most influential wireless technology in recent decades, a release said.
Born in Pollachi, Tamil Nadu, India, in 1944, Paulraj joined the Indian Navy when he was 15. Impressed with his academic record, the Navy sent him to IIT-Delhi, where he earned a PhD for advances to signal filtering theory. He served the Indian Navy for 25 years where he led the development of the APSOH sonar, one of India's most successful military development projects. He also founded three national laboratories in the areas of high-speed computing, AI and robotics, and military electronics.
He joined Stanford University in 1992, where he did all of his work on MIMO. He holds 79 patents and has won several global distinctions, including the two top global honors for telecom pioneers - the 2011 IEEE Alexander Graham Bell Medal and 2014 Marconi Prize and Fellowship.
Paulraj said it was his good fortune to have stumbled on the MIMO idea after some experiments at Stanford in 1992. "It took some years to convince DARPA (US Defence Advanced Research Project) and US industry to embrace the concept, but it finally got traction and is now the foundation of all wireless technology," he said.
He added that if he could contribute to India becoming a respected partner in the global wireless/ ICT eco-system, he would consider himself "truly blessed."
The US Patent and Trademark Office (USPTO) goes back to 1791 and has so far issued more than 8.8 million patents.
As of today, just 561 inventors have been inducted into its Hall of Fame, including Thomas Edison, the Wright Brothers, Alexander Graham Bell and Apple co-founder Steve Jobs.
Five Indian-origin scientists have been honoured in the past: CKN Patel (for the carbon dioxide laser), Jayant Baliga (insulated gate bipolar transistor), Haren Gandhi (automotive exhaust catalyst), Ashok Gadgil (UV water sanitation), and Rangaswamy Srinivasan (Lasik eye surgery). Mitra and Paulraj are among 15 innovation pioneers inducted in 2018.