EAScatter: Excitor-Aware Bluetooth Backscatter

We propose EAScatter, the first excitor-aware Bluetooth backscatter system with stable performance for different Bluetooth excitors. We first point out that the backscatter tag should fit the guard interval for different Bluetooth excitors. EAScatter uses a connection-based identification method, which can identify excitor during Bluetooth connection according to different shortest high level lengths. Thus, it can select a specific optimal guard interval for each excitor. Moreover, we introduce Plus-one modulation, which can further improve the goodput. We built a prototype of EAScatter and evaluated it with extensive experiments. EAScatter can achieve up to 98% identification accuracy. Using TI CC1352 as an excitor, it has a 25x PRR gain and a 28x goodput gain over the state-of-the-art RBLE.