Design and deployment of ESP-NOW wireless sensor networks for reliable smart farming applications

The increasing demand for smart farming has accelerated the use of Wireless Sensor Networks (WSNs) for smart farm data collection. Conventional wireless protocols such as Bluetooth, Zigbee and WiFi has limitations like high power consumption, short range, infrastructure dependence and high cost. These limitations restrict use of these protocols in designing WSNs for large-scale agricultural fields. This paper depicts an ESP-Now-based WSN as one of the best solution suitable for smart farm data collection system. It includes ESP32 sensor nodes which monitors real time environmental and soil parameters such as temperature, humidity, soil moisture, pH, smoke, light intensity, and animal activity in farm. Sensor nodes communicate via ESP-Now in a peer-to-peer, multi-hop configuration and forward data to a master ESP32. This collected data is transmitted to a Linux Machine for future predictions, local processing and cloud integration. A core contribution of this work is the experimental evaluation of ESP-Now protocol under three antenna configurations i.e. no antenna, 3 dB, and 5 dB. Field results show that using higher-gain antennas with ESP-Now can extend communication range more than 200 m while maintaining low latency and high packet delivery efficiency. The findings demonstrate that ESP-Now provides a scalable, energy-efficient, and cost-effective wireless backbone for precision agriculture in resource-constrained rural environments.