Computation and


Structures Group

Time Synchronization in Low Power Wide Area Networks


LoRaWAN is a low-cost, low-power wide area network (LPWAN) that is rapidly enabling battery-powered IoT devices in Smart Cities. LoRaWAN, however, is a low data rate, high latency protocol that prevents streaming of sensor data. In order to correlate events from widely spread sensors, devices must then keep track of time locally and transmit properly time-labeled events over the network.

We seek to implement a Time Synchronization Protocol over LoRaWAN and support coarse device synchronization of low-power clocks. We argue that synchronization is important not only in labeling events, but will also greatly improve the capacity of LoRaWAN's ALOHA-based protocol. The main challenge is to maintain the energy savings enabled by such a network and yet guarantee a level of synchronization accuracy defined by the applications.

This study aims to support our Traffic Calming research in collaboration with the City of Palo Alto, which presents such a use case for Time Synchronization over LPWANs. Contributions will be positioned as recommendations for inclusion in the LoRaWAN standard to further drive the development of LPWANs for Smart Cities overall.

Desired Outcomes for Semester

  • An Implementation of NTP over LoRaWAN
  • Evaluation of synchronization accuracy across LoRaWAN devices
  • Study the effects of synchronization on LoRaWAN channel capacity
  • Power analysis of synchronized devices in LoRaWAN


  • Must have taken 18-647, 18-747 or equivalent
  • Experience in C/C++
  • Experience working with the following is a plus:
    • ESP-32 or PowerDue
    • LoRa / LoRaWAN
    • Raspberry Pi
  • Version Control using Git


Send an email with your resume to: