About:

Passive wireless communication techniques enable extremely energy-constrained transmitters to send data by modulating RF sources that are ambient (e.g., TV broadcast transmissions) or generated by other devices that are not power-constrained (e.g., an RFID reader). These techniques have led to the development of ultra-low-power and even battery-free transmitters to enable various Internet of Things (IoT) applications. Compared to conventional wireless communication, backscatter is orders of magnitude more energy-efficient. However, one limitation of existing backscatter systems is their dependency on a nearby RF source, which means they are restricted to operating within meters of a base station, making it difficult for these solutions to operate in environments without existing infrastructure. Modulated Johnson Noise (MJN) communication holds promise to enable completely passive wireless communication without generating any RF source, and it operates by modulating the thermal (Johnson) noise power from an unpowered resistor. While the development of MJN communication is in its infancy, previous work has demonstrated that this communication technique can be a promising solution for a wide range of applications from contactless credit cards and stealthy communication to even satellite connectivity. To address this, I built a proof-of-concept wireless communication system using MJN in the nearfield band (13.56 MHz) with off-the-shelf, low-cost components in lieu of expensive software-defined radios. This work opens the door for using MJN in applications such as contactless payment and implantable sensors.

My Roles:

Built the hardware system using off-the-shelf components and manufactured 3D-printed rigs to control antenna distance

Performed signal processing techniques such as syncronous detection and filters using Python

Constructed the data encoding and collection pipeline on an MCU using C++

Selected to present this work at NSDI 2024 as a research poster to both industry and academia representatives

Click here to access full poster PDF