Nambirajan Seshadri

Nambirajan Seshadri
Nambirajan Seshadri
Associated organizations
AT&T Shannon Labs
Fields of study
Wireless communications
IEEE Alexander Graham Bell Medal


Nambi Seshadri’s pioneering research and commercial intuitiveness have impacted multiple generations of mobile and wireless communications and have helped make technology more affordable for consumers. While at AT&T Shannon Labs, one of Seshadri’s key research initiatives was his work on transmission and coding techniques using multiple transmit antennas. This helped create a new field of wireless communications called space-time coding that improved the reliability of data transmission. An earlier version of this work that he did at AT&T Bell Labs, called delay diversity, was an important component of the 2G cellular time-division multiple access systems and has also impacted WiFi and LTE systems. His contributions to reliable transmission of compressed speech over mobile radio channels also influenced the development of 2G cellular systems. He also drove the adoption of adaptive modulation and hybrid automatic repeat request techniques (important for high performance in time varying channels) in to the Enhanced Data Rates for Global Evolution (EDGE) standards. These techniques have become core to robust transmission in 3G and 4G systems around the world. His work on list Viterbi decoding and applications for combined speech and channel decoding as well as data transmission systems have been applied to improve speech quality in 2G and 3G systems. Following his career at AT&T Bell Labs and AT&T Shannon Labs, Seshadri helped build Broadcom into a significant player in the wireless market. Here, he initiated or nurtured projects such as short-range wireless, WiFi modems in phones, cellular modems, GPS, near-field communications, and the multimedia chip set strategy that resulted in pioneering products such as the high-definition video camcorder and advanced megapixel camera phones. Through his leadership, the company was able to reduce prices while improving the performance of wireless chipsets. This system-on-chip integration of applications processing, graphics, haptics, WiFi, Bluetooth, camera, and 2G/3G/4G modems has impacted the industry by making smart phones much more affordable.

An IEEE Fellow and member of the U.S. National Academy of Engineering, Seshadri is a professor of electrical and computer engineering at the University of California, San Diego, San Diego, CA and consulting CTO at Quantenna Communications, San Jose, CA, USA, in addition to serving as an advisor for several startups.