BMAR: Barometric and Motion-based Alignment and Refinement for Offline Signal Synchronization across Devices

Fig. 1. BMAR is a novel method to synchronize and align signals across devices without the need for specific user input, action, or explicit synchronization through wired or wireless communication (e.g., WiFi or BLE). BMAR is capable of synchronizing (a) independently recorded signals after the fact by (b) first pre-aligning recordings using air pressure as an inexpensive sensing modality that simultaneously allows us to reject non-simultaneous recordings. (c) In a second step, BMAR produces a refined signal alignment across sensor devices by cross-correlating accelerometer observations.