Large-scale agricultural monitoring relies on LoRa and LoRaWAN for long-range, low-power communication across vast terrains. However, single-hop architectures face coverage limitations in large or complex environments. Multi-hop LoRa improves connectivity through relay nodes but creates energy imbalance, as relay nodes handle both personal and forwarded transmissions, causing rapid energy depletion and threatening network sustainability. To systematically analyze this trade-off, we developed a reproducible simulation framework that compares single-hop and baseline two-hop LoRa architectures in a large-scale agricultural monitoring scenario. The evaluation employs key performance metrics, including network coverage, throughput, and energy consumption distribution among nodes. Simulation results demonstrate that the two-hop topology improves network coverage from 27.6% to 91.0% and increases total network throughput by more than four times compared to the single-hop configuration. These gains confirm the effectiveness of multi-hop communication in overcoming coverage constraints. However, the improved performance comes at a significant cost. Relay nodes in the two-hop architecture consume over twenty times more energy than standard end-nodes, revealing severe energy imbalance that compromises long-term network operation. This study highlights the trade-off in multi-hop LoRa architectures, showing that extended agricultural coverage requires energy-aware routing and load-balancing strategies to prevent premature relay node failure and ensure sustainable deployment.
Li et al. (Mon,) studied this question.