Ambuj Varshney
ambujv at nus dot edu dot sg

I am an engineer and an experimental computer scientist. I like to build real systems. I enjoy working at the intersection of electronics, computer science, and communication. More formally, I am an Assistant Professor in the School of Computing at the National University of Singapore . I am bootstrapping, Wireless, Embedded Intelligence, Sensing and Emerging Technologies (WEISER) group. I am part of the Systems and Networking area at School of Computing at National University of Singapore.

One of our major ongoing projects is to rethink factories of the future by enabling massive data collections, significantly increase the productivity, and usher in the next industrial revolution. This project is being conducted together with UC Berkeley (Prof. Prabal Dutta) and ABB. Our approach involves creating sticker form factor, and low power consumption sensors. There is even a possibility of powering these small computers with only the energy harvested from the environment, thus operating without batteries. You can read more about this project here.

A grant from the 2019 ABB Research Award supported my postdoctoral studies at the Department of Electrical Engineering and Computer Sciences (EECS) at the University of California, Berkeley.

I spent several wonderful years at Uppsala, Sweden, where I completed my PhD in Computer Science at Uppsala University . It is among the world's oldest institutions (est. 1477!), and oldest in Scandinavia.

I worked as a software engineer at NXP Semiconductor. I was responsible to design low-power wireless networking stack. Finally, I obtained a Bachelors in Information and Communication Technology from DA-IICT, India and I mostly worked under mentorship of Prof. Prabhat Ranjan.

I am a Swedish citizen 🇸🇪, and an Overseas Citizen of India 🇮🇳

I am actively looking for motivated Ph.D students, as well as undergraduates and visiting researchers.

Card Back Card Front

Prof. Dr. Ambuj Varshney
Department of Computer Science
School of Computing
National University of Singapore

Phone: +65 867 06948

Office address:
School of Computing
11 Research Link
Singapore 119391

Assistant (Admin/Scheduling):
C Kasinthra
  • [April 2022] I am serving as a session chair in IEEE INFOCOM 2022 (Conference) and CPS-IotBench 2022 (Part of CPS-IoT Week 2022 with ACM/IEEE IPSN 2022).
  • [March 2022] Our joint work with Wenqing Yan (Uppsala University) and Prof. Prabal Dutta (University of California, Berkeley) was accepted at ACM MobiSys 2022.
  • [March 2022] I am delighted to have returned to Asia (after almost ten years!). I am now an Assistant Professor at the Department of Computer Science@School of Computing , National University of Singapore
  • [January 2022] I am honoured to serve on the jury of the ABB Research Award in Honor of Hubertus von Grünberg in 2022 . Its research endowment (approximately 300k USD) is one of the highest offered by any commercial organization. You should consider applying for this prestigious grant if you are finishing your PhD studies, or have just recently completed your studies.
  • [November 2021] We will be presenting our work(done in collaboration with IMDEA Networks, Madrid, Spain ) at ACM MobiCom 2021 . We show that it is possible to wirelessly transmit to distances of hundreds of meters while using few microwatts of power. We achieve this by designing a hybrid light and RF backscatter system. The work is available here . It has also been covered by several media outlets: Hackster , El Mundo (Largest newspaper in Spain) , Stacey on IoT , TechXplore , AzoSensors, ElectronicsForu
  • [September 2021] I am a University of California, Berkeley - Form+Fund Fellow for 2021. I have been selected for a highly selective and prestigious fellowship for the Spring 2021 cohort.
  • [April 2021] I am excited to serve on the editoral board of the "Wireless Embedded Systems" track of the exciting new open-access journal Journal of Systems Research"
  • [August 2020] Looking forward to beginning a new chapter in my career as a Postdoctoral Scholar at the University of California, Berkeley under the guidance of Prof. Prabal Dutta.
  • [June 2020] Extremely proud that Andreas Soleiman whom I have been mentoring for past several years has received Ph.D. admits from University of California@Berkeley, MIT (accepted), University of Washington@Seattle, Dartmouth and others!!
  • [December 2019] Uppsala University Innovation appreciated our battery-free sensing work with Attractive Innovation Award and selected it among Top 15 projects from the University! Find the press release here
  • [November 2019] For my doctoral dissertation and ongoing work to enable large-scale data collection in industries with battery-free sensors, I received the prestigious ABB Research Award 2019. The award includes the highest endowment contribution from any company, valued at 300,000 USD. You can read more about this from the following press release from ABB, and another press release from Uppsala University.
Blog Posts
Get to know more about my research (2019 ABB Research Award Video):


I take great pride in mentoring students. I have been fortunate to mentor following students (formally):

  • Andreas Soleiman (2016-2019) [RA, Master thesis] → MIT EECS PhD (withdrew to stay in industry)
  • Elena di Lascio (2015-2016) [Master thesis] → USI PhD (completed) → Novartis Institutes for BioMedical Research (NIBR)
  • Oliver Harms (2016-2017)[Master thesis] → Chalmers PhD
  • Gustav Eriksson (2018)[Masters Thesis] → Project Engineer
  • Sam Hylamia (2017-2018)[Masters Thesis and Research Assistant] → Uppsala University PhD
  • Simon Olofsson (2015)[Project assistant] → Imperial College London PhD → Facebook/Meta

I have also been very fortunate to collaborate with the following students:

Service to the academic community
Invited and Conference Talks
  • [March 2022] I am giving an invited talk at ACM LP-IoT 2021 (co-located with ACM MobiCom 2021) . Please register to attend the talk and event. We are going to discuss future of wireless for IoT devices.
  • [October 2021] Together with Revathy Narayanan (Experienced Researcher@Ericsson Research, Stockholm), We presented our work on fingerprinting backscatter transmissions at ACM HotNets 2021 (online)
  • [March 2021] I was invited to give a talk at Department of Computing @ Imperial College London . My faculty host in the department was Professor Kin Leung
  • [March 2021] I was invited to give a talk at ETH Zurich . My faculty host was Professor Laurent Vanbeever
  • [March 2021] I gave an invited talk at National University of Singapore. My host was Professor Mun Choon Chan
  • [March 2021] I gave an invited talk at IMDEA Network Institute, Spain. My host was Professor Sergey Gorinsky
  • [March 2021] I gave an invited talk at give a talk at Aalto University, Finland.
  • [February 2021] I gave a talk at KTH, Stockholm, Sweden. Due to the pandemic, I took leave of absence from UC Berkeley, and I visited the NSS Group @KTH. The talk was delivered during the visit to the research group.
  • [November 2020] I worked together with colleagues at the IMDEA Networks Institute in Spain. At European Researchers' Night 2020 and Science and Innovation Week 2020, we presented work on designing battery-free platforms using hybrid (RF-backscatter and LiFi) communication mediums. Watch more in this video.
  • [October 2020] ACM SIGMOBILE India Chapter invited me to speak about enabling widespread sustainable sensing. The announcement was distributed through official ACM channels.
  • [October 2020] At ACM MOBICOM 2020, I presented our work on low-power carrier emitters using tunnel diode. The research was conducted jointly with Lorenzo Corneo (Uppsala University). Watch the presentation here .
  • [July 2020] At ACM MOBISYS 2020, I presented a hybrid light and RF backscatter system. We did this work with colleagues at the IMDEA Networks Institute in Spain. You can find video presentation here .
  • [February 2020] I was invited to give a talk at ABB Corporate Research Center, Sweden. I discused enabling sustainable and widespread sensing in factories. My host for the talk was Dr. Alf Isaksson (ABB Research Fellow)
  • [November 2019] I gave a talk at ABB Research Center, Baden, Switzerland. It was (among others) attended by the CEO and Chairman of ABB, Peter Voser , and Ex-chairman of ABB, Hubertus von Gruenberg.
Selected Publications

Making Low-power and Long-range Wireless Backscatter Transmitters
Ambuj Varshney
ACM GetMobile: Mobile Computing and Communications (Maker Edition) 2022 (To appear)

Judo: Addressing the Energy Asymmetry of Wireless Embedded Systems through Tunnel Diode based Wireless Transmitters
Ambuj Varshney* , Wenqing Yan*, Prabal Dutta
*Co-primary author contributing equally to the work
The Twentieth ACM International Conference on Mobile Systems, Applications, and Services (ACM MobiSys 2022)

PassiveLiFi: Rethinking LiFi for Low-Power and Long Range RF Backscatter
Muhammad Sarmad, Borja Genoves, Ambuj Varshney , Domenico Giustiniano
The Twenty Seventh Annual International Conference On Mobile Computing And Networking (ACM MobiCom 2021/2022)
(Due to the pandemic, the conference was held in 2022)

Securing Battery-free Backscatter Tags through Fingerprinting
Revathy Narayanan , Ambuj Varshney , Panos Papadimitratos
The Twentieth ACM Workshop on Hot Topics in Networks (ACM HotNets 2021)

Radio frequency communication device for low power communication
Ambuj Varshney (Only inventor)
[PCT/Patent Application] [WO2021040594A1]

Tunnel Emitter: Tunnel Diode based Low-Power Carrier Emitters for Backscatter Tags
Ambuj Varshney , Lorenzo Corneo
The Twenty Sixth Annual International Conference On Mobile Computing And Networking (ACM MobiCom 2020)

Two to Tango: Hybrid Light and Backscatter Networks for Next Billion Devices
Ander Galisteo*, Ambuj Varshney* , Domenico Giustiniano
* Co-primary author that contributed equally to the work
The Eighteenth ACM International Conference on Mobile Systems, Applications, and Services(ACM MobiSys 2020)

TunnelScatter: Low Power Communication for Sensor Tags using Tunnel Diodes
Ambuj Varshney , Andreas Soleiman , Thiemo Voigt
The Twenty Fifth Annual International Conference On Mobile Computing And Networking (ACM MobiCom 2019)

Connecting Battery-free IoT Tags Using LED Bulbs
Domenico Giustiniano , Ambuj Varshney, Thiemo Voigt
The Eighteenth ACM Workshop on Hot Topics in Networks (ACM HotNets 2019)

Demonstration: Towards Battery-free Radio Tomographic Imaging
Abdullah Hylamia, Ambuj Varshney , Andreas Soleiman, Panos Papadimitratos , Christian Rohner, Thiemo Voigt
The Eleventh ACM Conference on Security and Privacy in Wireless and Mobile Networks (ACM WiSec-2018)
Best demonstration award

Battery-free 802.15.4 Receiver
Carlos Perez Penichet, Claro Noda, Ambuj Varshney , Thiemo Voigt
The Seventeenth ACM/IEEE Conference on Information Processing in Sensor Networks.(ACM/IEEE IPSN 2018)

Enabling Sustainable Networked Embedded Systems
Ambuj Varshney, Doctoral dissertation
Awarded the 2019 ABB Research Award in Honour of HvG (with grant of 300k USD)
Press release from Uppsala University
Press release from ABB

LoRea: A Backscatter Architecture that Achieves a Long Communication Range
Ambuj Varshney , Oliver Harms, Carlos Penichet, Christian Rohner , Frederik Hermans, Thiemo Voigt
The Fifteenth ACM Conference on Embedded Networked Sensor Systems (ACM SENSYS 2017)
2019 ABB Research Award Winner

Battery-free Visible Light Sensing
Ambuj Varshney, Andreas Soleiman, Luca Mottola, Thiemo Voigt
(ACM VLCS (Co-located with ACM MobiCom) 2017 )
Best Paper Award
ACM Student Research Competition Winner (Graduate, MobiCom) (Mentored student)
Google Faculty Research Award 2018 (PhD advisor)

Towards wide-area backscatter networks
Ambuj Varshney , Carlos Perez Penichet, Christian Rohner, Thiemo Voigt
(ACM HotWireless (Co-located with ACM MobiCom) 2017)

modBulb: A Modular Light Bulb for Visible Light Communication
Kasun Hewage, Ambuj Varshney , Abdalah Hilamia, Thiemo Voigt
(ACM VLCS (Co-located with ACM MobiCom) 2016)

Augmenting IoT Networks with Backscatter-Enabled Passive Sensor Tags
Carlos Perez Penichet, Frederik Hermans, Ambuj Varshney , Thiemo Voigt
(ACM HotWireless (Co-located with ACM MobiCom) 2016)

Directional Transmissions and Receptions for High-throughput Bulk Forwarding in Wireless Sensor Networks
Ambuj Varshney , Luca Mottola, Mats Carlsson , Thiemo Voigt
The Thirteenth ACM Conference on Embedded Networked Sensor Systems (ACM SENSYS 2015)

dRTI: Directional Radio Tomographic Imaging
Bo Wei , Ambuj Varshney , Wen Hu, Neal Patwari, Thiemo Voigt , Chun Tung Chou
The Fourteenth ACM/IEEE Conference on Information Processing in Sensor Networks(ACM/IEEE IPSN 2015)

This guy makes a nice webpage.