Synchronous LoRa Communication by Exploiting Large-Area Out-of-Band Synchronization

Many new narrowband low-power wide-area networks (LPWANs) (e.g., LoRaWAN, Sigfox) have opted to use pure ALOHA-like access for its reduced control overhead and asynchronous transmissions. Although reduces the energy consumption of IoT devices, network performance suffers from high intra-network interference in dense deployments. Contrarily, synchronous can improve throughput fairness, but it requires time synchronization. Unfortunately, maintaining synchronization over LPWANs wastes channel transmission opportunities. In this paper, we propose out-of-band time-dissemination relatively synchronize LoRa devices thereby facilitate resource-efficient slotted uplink communication. To end, conceptualize analyze a co-designed random mechanism that effectively exploit technologies providing limited accuracy, such as FM radio data system (FM-RDS). While considering LoRa-specific parameters, derive proposed mechanism, compare generic using in-band synchronization, design communication parameters under uncertainty. We scrutinize uncertainty device by introducing clock error model accounts errors source, local clock, propagation delay, transceiver's characterize FM-RDS with hardware measurements perform simulations evaluate solution. The results, presented terms success probability, throughput, fairness single-cell scenario, suggest FM-RDS, despite poor absolute be used realize similar more accurate technologies.