Design Of A Communication System To Send Text Using Lora At 400 MHz

This work describes the design and implementation of a low-power wireless communication system for transmitting text using ESP32 modules and the LoRa DXLR01. The proposal arises as a solution to connectivity and energy-efficiency problems commonly found in rural areas and certain urban environments where Wi-Fi or mobile networks are unavailable or operate with limitations. To address this, LoRa technology known for its long-range capability and low power consumption is integrated with an ESP32 responsible for capturing, processing, and sending messages. The LoRa DXLR01 module, which operates in the 433 MHz band, is configured with parameters aimed at maximising both transmission range and efficient energy usage. Messages are sent using Chirp Spread Spectrum (CSS) modulation, improving signal penetration in obstructed areas and reducing the likelihood of errors. On the receiving end, the ESP32 interprets the data and displays it on an LCD screen. Additionally, the received information is sent to the ThingSpeak platform, allowing remote storage and visualisation without relying on conventional network infrastructure. Tests conducted in a controlled environment show an average latency of 3.2 seconds for text transmission. It was also verified that the system can be used in applications such as remote monitoring, infrastructure management, and access control.