Postdoctoral Scholar
Lab 11 (Led by Prof. Prabal Dutta )
Department of Electrical Engineering and Computer Science
University of California, Berkeley
Email address:

You can find my resume and research statement here


I am a postdoctoral scholar working under the mentorship of Prof. Prabal Dutta at Department of Electrical Engineering and Computer Sciences at University of California, Berkeley.

I plan to start as an Assistant Professor at Department of Computer Science at National University of Singapore in 2022.

Prospective students: feel free to reach out to me!

Research Interests:

My research interests centers around designing and tackling challenges of embedded -- sensing, communication and computation -- systems. I take an interdisciplinary approach of combining the concepts in communication, computer science and electronics to design embedded systems and applications. I enjoy working at their intersection.

In the recent few years, the focus of my research has been around designing sensing and communication systems that can operate at very low power which makes it possible to operate these systems on tiny batteries, or even without batteries on minuscle amounts ofenergy harvested from the ambient environment. E.g., As part of my postdoctoral work, I am working on designing low-power sensors to enable large scale data collection for future factores. The low-power may even enable these sensors to operate without batteries! Check this video (ABB produced video). You can also read more about me here , and in swedish here .

Prior Background:

Before joining UC Berkeley, I spent several years at Uppsala University, Sweden, where I also obtained my Ph.D degree. During my time at Uppsala University, I shephereded the move of the research group from classical wireless sensor networks towards emerging communication areas (Backscatter, LiFi, Tunnel Diodes).

Before joining Uppsala University, I worked at NXP Semiconductors, where I was responsible to design low-power wireless networking stack. Some of my work conducted at NXP was also shipped to the customers. I obtained a Bachelors degree in Information and Communication Technology, and during my studies, I primarily worked with Prof. Prabhat Ranjan, and I studied and developed interest in electronics, computer science, and communications, and designed wireless cameras to take images of tigers!



Selected Publications

Securing Battery-free Backscatter Tags through Fingerprinting
Revathy Narayanan , Ambuj Varshney , Panos Papadimitratos

PassiveLiFi: Rethinking LiFi for Low-Power and Long Range RF Backscatter
Muhammad Sarmad, Borja Genoves, Ambuj Varshney , Domenico Giustiniano

Tunnel Emitter: Tunnel Diode based Low-Power Carrier Emitters for Backscatter Tags
Ambuj Varshney , Lorenzo Corneo
Find the conference video presentation here!

Two to Tango: Hybrid Light and Backscatter Networks for Next Billion Devices
Ander Galisteo* , Ambuj Varshney* , Domenico Giustiniano .
* Co-primary authors contributing equally to the work
Find the conference video presentation here!

TunnelScatter: Low Power Communication for Sensor Tags using Tunnel Diodes
Ambuj Varshney , Andreas Soleiman , Thiemo Voigt
Find the conference video presentation here!

Connecting Battery-free IoT Tags Using LED Bulbs
Domenico Giustiniano , Ambuj Varshney, Thiemo Voigt

Demonstration: Towards Battery-free Radio Tomographic Imaging
Abdullah Hylamia, Ambuj Varshney , Andreas Soleiman, Panos Papadimitratos , Christian Rohner, Thiemo Voigt
Best Demonstration Award!!

Battery-free 802.15.4 Receiver
Carlos Perez Penichet, Claro Noda, Ambuj Varshney , Thiemo Voigt

LoRea: A Backscatter architecture that achieves a long communication range
Ambuj Varshney , Oliver Harms, Carlos Penichet, Christian Rohner , Frederik Hermans, Thiemo Voigt
2019 ABB HvG Award Winner

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

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 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

dRTI: Directional Radio Tomographic Imaging
Bo Wei , Ambuj Varshney , Wen Hu, Neal Patwari, Thiemo Voigt , Chun Tung Chou


Academic Service

You can read more about my involvement in academic community here .


You can find some of my talks and coverage of my work in the media here .


I take great pride in mentoring students, and am fortunate to be able to mentor the students listed below (alumni, not present):

Awards and Grants


You can read more about my teaching activities here.

Misc Other

Even before: My first computer was a IBM PC XT back in 1992. I have been supporter and follower of FOSS movement and Linux since 1998. I contributed to IndLinux project and traslated many applications to Hindi back in 2000-2001. From 2006, I was maintaining a blog called Linux on Desktop where I discussed the use of GNU/Linux on desktops. At that time, it was ranked as Top-10 blog in the genre and I used the revenue from the Google Advertisements (Adsense) on the blog posts to fund my undegraduate education. In 2010, I briefly worked with PlayPower project (From Carnegie Mellon University with Derek Lomas), and developed games for 6502 microcontroller.