DFRobot Gravity LoRaWAN Node Module SX1262 US915

Connect the module's VCC (3.3V-5V), GND, TX, and RX pins to the Arduino's corresponding pins. Use a software serial library on an unused pin pair if needed. Install the required LoRa library (like MCCI LoRaWAN LMIC or Sandeep Mistry's library) in the Arduino IDE. Configure the sketch with your LoRaWAN keys (AppEUI, DevEUI, AppKey) for OTAA activation or use ABP. Set the correct US915 frequency plan and sub-band in the library configuration files before uploading.

In LoRa point-to-point mode, two modules communicate directly with each other using raw LoRa modulation, which is simpler and suitable for private, device-to-device links. LoRaWAN mode connects the module to a LoRaWAN network server (like The Things Network) via gateways, enabling secure, scalable, and bidirectional communication with cloud applications. The module supports LoRaWAN Class A (low-power, uplink-initiated) and Class C (continuously listening for downlinks). You typically select the mode via AT commands or within your embedded firmware library settings.

The module has an integrated PCB antenna. For extended range, you can solder a wire antenna to the designated pad or connect an external 915MHz antenna via an IPEX/U.FL connector if present. Use a matched 50-ohm antenna like a dipole or whip with approximately 3dBi gain. Ensure the antenna is elevated and has a clear line of sight. Configure the transmit power to the maximum +22 dBm in your firmware, but be mindful of local regulatory limits. Optimal range also depends on spreading factor (SF) and bandwidth settings; higher SF increases range but reduces data rate.

The module's operating current varies with transmit power; expect ~120mA during transmission at +22 dBm and ~5mA during active reception. In sleep mode, current drops to microamps. To implement battery-saving operation, use the module's built-in low-power commands. In your firmware, after sending data, put the SX1262 chip into deep sleep via the appropriate library function or AT command. Wake the module periodically using a hardware timer interrupt on your host MCU. Power the entire node from a 3.3V regulator and use a high-capacity Li-ion battery coupled with a solar charger for long-term field deployment.