The goal of this project is to create low-power backscatter and radio devices and designing network protocols and PHY innovations that will allow a large number of these devices to transmit concurrently. To this end, the team has built a number of novel systems.

Netscatter: We designed the first wireless protocol that can scale to hundreds and thousands of concurrent transmissions from backscatter devices. Our design enables concurrent transmissions fro 256 devices over a bandwidth of 500 kHz. Consequently, it can support transmissions from a thousand concurrent backscatter devices using 2 MHz.

TinySDR: We created the first software-defined radio platform for power-constrained IoT endpoints. It is a standalone, fully programmable low power software-defined radio solution that can be duty cycled for battery operation like a real IoT endpoint and can be programmed over the air to allow for large scale deployments. Open source code: https://github.com/uw-x/tinysdr

BeetleCam: We created a fully wireless, power-autonomous, steerable vision system. Our electronics and actuator weight 248 mg and can steer the camera over 60 degrees. The camera streams ``first person" 160X 120 monochrome video at 1-5 fps to a Bluetooth radio from up to 120 meters away.  Our results demonstrate that steerable vision can enable object tracking and wide-angle views for 26 to 84 times lower energy than moving the whole device. Open source code: https://github.com/uw-x/insect-robot-cam

Airdropping wireless sensors: We presented the first system that can airdrop wireless sensors from small drones and live insects. In addition to the challenges of achieving low-power consumption and long-range communication, air-dropping wireless sensors is difficult because it requires the sensor to survive the impact when dropped in mid-air. Our design takes inspiration from nature: small insects like ants can fall from tall buildings and survive because of their tiny mass and size. Inspired by this, we design insect-scale wireless sensors that come fully integrated with an onboard power supply and a lightweight mechanical actuator to detach from the aerial platform. Our system introduces a first-of-its-kind 37 mg mechanical release mechanism to drop the sensor during flight, using only 450𝜇J of energy as well as a wireless communication link that can transmit sensor data at 33 kbps up to 1 km. Once deployed, our 98 mg wireless sensor can run for 1.3-2.5 years when transmitting 10-50 packets per hour on a 68 mg battery. Open-source code: https://github.com/uw-x/airdrop-sensors

Dandelion sensors: We demonstrated wind dispersal of battery-free wireless sensing devices. Our millimetre-scale devices weigh 30 milligrams and are designed on a flexible substrate using programmable, off-the-shelf parts to enable scalability and flexibility for various sensing and computing applications. The system is powered using lightweight solar cells and an energy harvesting circuit that is robust to low and variable light conditions, and has a backscatter communication link that enables data transmission. Open-source code: https://github.com/uw-x/wind_dispersal