Arduino Uno + LoRa RA-02 Temperature Sensor

Wireless Communication is evolving day by day. Many advanced low power communication technologies are emerging across the globe. One such technology is LoRa, which stands for Long Range. It consumes very less power and has long transmission ranges. This project demonstrates the basic usage of LoRa RA-02 Module. Make sure that you check the frequency band as it varies from country to country.

We'll use LoRa RA-02 to transmit temperature values read by a temperature sensor from Arduino UNO to another Arduino UNO and display on the Serial Monitor. Values will be transmitted at an interval of 5 seconds.

I would recommend ( and use ) the breakout board type as it is easy to use and breadboard friendly. Before starting the project, we have to solder the header pins on the LoRa Breakout board. Be careful not to overheat the board.

We have a special library for LoRa developed by Sandeep Mistry. I'm using the same library for my LoRa projects. It can be found here.

This project is divided into two parts : Transmitter and Receiver part.

LoRa Transmitter :

• Temperature sensor sends analog signal proportional to the measured temperature, which is fed to the analog pin of Arduino UNO.
• Arduino UNO does the required calculations for conversion of signal to temperature in Celsius or Farenhite.
• Arduino UNO uses SPI protocol to communicate with LoRa module, which transmits the measured temperature values every 5 seconds.

Temperature Sensor Pin Description

Pin Connections :

LoRa Receiver :

• LoRa module reads the received message packet and transfers the packet to Arduino UNO using SPI protocol.
• Arduino UNO reads the packet and displays the message on Serial Monitor.

Pin connections :

Implementation

Test Output on Serial Monitor

Note :

• To increase communication range, an antenna can be connected to the LoRa Module.
• If all the Ground pins of LoRa module are not grounded, it might hang the system or give erroneous message signals at output.