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

Indian engineer and scientist Arogyaswami Paulraj’s journey from developing indigenous sonar for the Indian Navy to pioneering MIMO technology illustrates the far-reaching impact of research. His APSOH sonar project strengthened India’s underwater detection capabilities, while his later work at Stanford transformed wireless communication. MIMO became a foundation of high-speed connectivity used in 4G, 5G and Wi-Fi. Paulraj’s career highlights how persistence, fundamental research and unexpected discoveries can produce technologies that reshape everyday life.