IIT Delhi engineer built India’s sonar in 1971: How his MIMO changed 4G, 5G

In 1971, a naval officer was asked to solve a problem that India could not simply buy its way out of. The Indian Navy needed better anti-submarine sonar, but access to advanced foreign systems was restricted. The officer tasked with finding an indigenous solution was Arogyaswami Paulraj.Decades later, the technology he pioneered would have a very different application. Paulraj's work on MIMO — multiple-input, multiple-output wireless communication — became a foundation of modern high-speed wireless networks, including 4G, 5G and Wi-Fi. Stanford University describes his MIMO work as laying the foundation for today's high-speed wireless connectivity.From the Indian Navy to IIT DelhiBorn in Pollachi, Tamil Nadu, in 1944, Paulraj joined the Indian Navy as a teenager. The Navy recognised his academic ability and sent him to IIT Delhi for advanced studies.