Mighty: Towards Long-Range and High-Throughput Backscatter for Drones

Abstract

While small drone video streaming systems create unprecedented video content, they also place a power burden exceeding 20% on the drone's battery, limiting flight endurance. We present ${\sf Mighty}$, a hardware-software solution to minimize the power consumption of a drone's video streaming system by offloading power overheads associated with both video compression and transmission to a ground controller. ${\sf Mighty}$ innovates a high performance co-design among: (1) a ring oscillator-based, ultra-low power backscatter radio; (2) a spectrally-efficient, non-linear, low-power physical layer modulation and multi-chain radio architecture; and (3) a lightweight video compression codec-bypassing software design. Our co-design exploits synergies among these components, resulting in joint throughput and range performance that pushes the known envelope. We prototype ${\sf Mighty}$ on PCB board and conduct extensive field studies both indoors and outdoors. The power efficiency of ${\sf Mighty}$ is about 16.6 nJ/bit. A head-to-head comparison with a DJI Mini2 drone's default video streaming system shows that ${\sf Mighty}$ achieves similar throughput at a drone-to-controller distance of up to 150 meters, with 34–55× improvement of power efficiency than WiFi-based video streaming solutions.