Q&A: Meet the Award-Winning UC San Diego Alumnus Shaping Wireless Tech

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Raghav Subbaraman (’24), a Ph.D. graduate from the University of California San Diego Jacobs School of Engineering, recently won a Paul Baran Young Scholar Award from the Marconi Society, a nonprofit that promotes global connectivity and sustainability. The award recognizes individuals 27 years of age or younger who have demonstrated outstanding scientific achievements, leadership and entrepreneurial spirit in advancing the connected world. In this Q&A, the honoree chats about his accomplishments, his experience at UC San Diego and how his graduate training laid the foundation for his current job at Apple. (This interview has been edited for length and clarity.)

Congratulations on receiving the Paul Baran Young Scholar Award! That’s quite an honor.

Thank you!

What are you doing now? You’re working as an engineer for Apple?

Yes, I’m working at Apple on the Wi-Fi team, where I do some R&D and engineering for Wi-Fi features. While I can’t talk about the specifics, my work basically touches all of Apple’s Wi-Fi-enabled platforms — iPhones, iPads, Macs. I use the work I did at UC San Diego and the exposure that I got at QI and other places on a day-to-day basis. While it’s not exactly the same, the same concepts and first principles apply. That’s something I am happy about.

When were you at UC San Diego?

I was an intern at QI in 2018 with Professor Bharadia, then a Ph.D. student in his group from 2019 to mid-2024. My major was in communication theory and systems, and I defended my dissertation in mid-2024. I interacted with many people at QI. We had collaborations with Professor Ramesh Rao [QI’s director] and others. All of those experiences were awesome—each and every bit. I also collaborated with interdisciplinary groups like Sysnet (Computer Science and Engineering, UC San Diego)

Could you give me a layperson’s explanation of the work you did in graduate school?

Our wireless devices communicate by accessing a shared resource: the radio frequency spectrum. Most people know about spectrum auctions where big providers like AT&T and Verizon shell out a lot of money to buy spectrum from the government. An easy analogy would be land. These spectrum slices are like pieces of land that companies lease from the government to provide services like internet connectivity and cell phone plans. Government and other private entities also use spectrum. The Department of Defense uses it for national security purposes; the Meteorology Department sends out wireless signals to the sky to monitor clouds.

There are many uses for wireless spectrum, and many people want access. Since this is a limited resource, we need to ensure that access is fair, properly regulated and efficient, as well as secure, so bad actors don’t leak information.

In my dissertation, I built systems that allow us to visualize and understand how the spectrum is being used in real-time. I built hardware systems that plug into a computer so you can look at different frequency bands — Who’s using that? What are they using it for? — and gain insights from that. I also showed how some of those insights can be distilled into actionable information to improve the utilization of this resource.

How did you get into this field? Is it something you’ve pursued for a long time?

When I was an undergrad, I worked on a 5G testbed project. During that time, I was given something called a spectrum analyzer, which is a device that helps you visualize the spectrum, albeit in a more rudimentary way than the systems I designed and developed. When I looked at a spectrum analyzer for the first time, I was able to see what wireless signals look like. Ever since, that has been my go-to tool for debugging and for better understanding what is going on. I would pick up a spectrum analyzer and start from there, bottom up. That somehow continued into my Ph.D. work. My quirky desire to view how chatty our wireless devices are ended up being my full-time job for five years. I’m happy about that, because I still stare at some of the outputs of these systems I’ve built, and I learn something new almost every time. What is this small thing going on over here? It turns out to be my car key, and now I can examine what the signals from my car keys look like. Then I might wonder, “Can I record them and replay them and somehow hack my car?” One thing leads to another.

Where were you as an undergraduate?

I did my undergraduate studies at the Indian Institute of Technology Madras, in Chennai, India. I met Professor Bharadia there when he came to give a talk. That’s how I came to UC San Diego for an internship.

Was it a deliberate decision to come to the United States, or were you drawn to Dinesh Bharadia’s lab in particular?

The kind of research that Professor Bharadia did was quite new when I joined him. He had only been at UC San Diego for about a year, and his work on full duplex communication and wireless systems was already seminal in the field. I really respected and was inspired by the kind of work he did, so UC San Diego was one of my first choices. And once you come to La Jolla and experience the campus, it’s difficult to go anywhere else.

Is there anything else you want people to know about your journey?

At QI, Professor Bharadia’s lab and the larger UC San Diego Jacobs School of Engineering, the peer group was very good. I had a lot of support from my lab mates and colleagues, not just from my advisor. That was very important. As far as communication and wireless systems are concerned, I would 100% choose UC San Diego all over again. I could shout from tall buildings, “Hey, you guys should go to UC San Diego to learn this.” My experience was really great.

Learn more about graduate studies at the UC San Diego Jacobs School of Engineering, internships at the UC San Diego Qualcomm Institute, and research in Associate Professor of Electrical and Computer Engineering Dinesh Bharadia’s Wireless Communications Sensing and Networking group.