You can find a paper discussing about how to use a microprocess (possible to implement on Arduino) to design a LoRa Mesh Wireless Network
- Huang-Chen Lee, Kai-Hsiang Ke, Monitoring of Large-Area IoT Sensors using a LoRa Wireless Mesh Network System: Design and Evaluation, IEEE Transactions on Instrumentation & Measurement, accepted, Mar 2018.
Good luck!