Communication) In this project, you will construct a sensor monitoring system using a TTGO LoRa32 SX1276 OLED board. This board will send readings of temperature, humidity, and pressure via LoRa radio to an ESP32 LoRa receiver that you will build yourself. The most recent sensor readings can be viewed on a web server thanks to the receiver. Over the course of the past few years, a variety of communication technologies have become available for use in the interaction of Internet of

Things devices. The Wi-Fi Technology and the Bluetooth Module are two of the most well-known examples. However, they have a few drawbacks, such as a restricted range, a restricted number of access points, and a high level of power consumption. Therefore, Semtech developed the LoRa technology in order to resolve all of these problems. This device can run for over a year on a single battery even though it only requires one. As a result, in this Internet of Things project, we will design an ESP32 LoRa Web Server to enable wireless monitoring of sensor readings from distances of several kilometers. The DHT11 Sensor will be used to read the data pertaining to the relative humidity and temperature by the sender. After that, it sends the data out using a LoRa Radio. The data is obtained through the receiver module, which is the component responsible for housing the OLED Display. The receiver has the ability to link the device to a WiFi network so it can communicate with other devices. The IP Address will be displayed on the OLED screen. You can log into any web browser where the sensor reading is monitored by using the IP address.

The image that follows provides a high-level overview of the project that we will construct throughout the entirety of this project.

Readings from the BME280 sensor are transmitted over the LoRa radio by the LoRa sender every ten seconds. The readings are obtained by the LoRa receiver, which then displays them on a web server; Accessing the web server will allow you to monitor the readings from the sensors; Depending on where both the LoRa sender and the Lora receiver are situated, there may be a distance of several hundred meters between the two devices. Therefore, if your fields or greenhouses are located some distance from your house, you can use this project to monitor sensor readings from those locations;

The LoRa receiver operates as an asynchronous web server, and the files for the web page are stored on the ESP32 filesystem (SPIFFS). The LoRa receiver also displays the date and time that the most recent readings were obtained. Utilizing the Network Time Protocol on the ESP32 allows us to obtain the current date and time.

The following elements will be utilized in the completion of this project: TTGO LoRa32 SX1276 OLED board (2x): this is a development board for the ESP32 platform that incorporates an OLED display and a LoRa chip. You can use boards that are similar to what you already have, or you can use an ESP32, LoRa chip, and OLED individually. BME280 sensor for measuring temperature, humidity, and pressure It ought to be possible for you to adapt this project so that you can use any other sensor. Preparing the Arduino IDE We will be using Arduino IDE as our programming environment for the TTGO LoRa32 SX1276 OLED boards. We are going to make use of the ESP32 filesystem uploader plugin in order to transfer files to and from the ESP32 filesystem. Installing libraries You will need to download and install a few different libraries for this project. Library support for LoRa, BME280, and OLED The Arduino Library Manager allows you to install any of the following libraries on your computer. Find the library's name by

going to Sketch > Include Library > Manage Libraries and searching for it there. Sandeep Mistry's Arduino-LoRa library is referred to as the LoRa library. Both the Adafruit SSD1306 library and the Adafruit GFX library are OLED libraries. Adafruit BME280 library and Adafruit unified sensor library are two examples of BME280 libraries.

LoRa Sender Circuit

The I2C communication protocol is utilized for conversation between the BME280 and the ESP32 that we are using. Connect the sensor's wires in the

Testing the LoRa Sender Transfer the code to the ESP32 LoRa Sender Board that you are using. Select the COM port it is connected to by going to the Tools menu and selecting the Port option. Then, select the board you want to use by going to the Tools menu and selecting Board. In our situation, we are utilizing the TTGO LoRa32-OLED V1. To finish, click the button labeled "Upload." Start up the Serial Monitor with the baud rate set to 115200. You need to obtain something similar to what is shown below.

It is expected that the most recent sensor readings will be displayed on the OLED of your board. Your LoRa Sender is prepared and ready to go. Let's move on from here and talk about the LoRa Receiver. LoRa Receiver The LoRa Receiver is responsible for receiving incoming LoRa packets and displaying the readings that it has received on an asynchronous web server. In addition to the readings from the sensors, we show the most recent time that these readings were received as well as the RSSI (received signal strength indicator).

Launch a web browser and enter the IP address of your ESP32. You ought to be able to view the most recent sensor readings on the web server. In open field, we were able to maintain a stable LoRa communication using these boards for a distance of up to 180 meters (590 feet). This indicates that the sender and receiver can be located at a distance of 180 meters from

one another, and we will still be able to get and check the readings on the web server. It is really impressive that stable communication can be maintained at a distance of 180 meters using boards with such low costs and without any additional customization.

Nevertheless, in a previous project we used an RFM95 SX1276 LoRa transceiver chip with a homemade antenna, and we obtained better results: a range of more than 250 meters despite the presence of many obstructions in between. The communication range will be determined largely by the environment in which the LoRa board is being used along with a great deal of other factors. By incorporating solar panels and a deep sleep mode into your LoRa sender, you can expand the functionality of this project and create a monitoring system that operates independently from the grid.