| Popis: |
Besides the communication function, wireless signals are recently exploited for sensing purposes, enabling diverse applications. However, designing a wireless sensing system that provides truly pervasive coverage at city or even national scale and at the same time does not affect ongoing data communication is still challenging. In this work, we propose to involve the pervasive LTE signals into the ecosystem of wireless sensing. Although LTE sensing solves the coverage issue and does not compromise the communication function, it brings unique challenges. Due to the long distance between LTE base stations and terminals, the LTE signal interacts with diverse objects during the propagation process which causes severe interference in sensing. We enable LTE sensing by designing delicate signal processing schemes to combat against the severe interference. We demonstrate the advantages of LTE sensing using two typical applications, indoor respiration sensing and outdoor traffic monitoring. Extensive experiments show that the proposed system can achieve highly accurate respiration sensing with the blind spot and orientation-sensitive issues greatly mitigated. For traffic monitoring, the error of car speed estimation is lower than 2 mph, as good as commercial devices on the market. |
