Efficient, low-cost prototype drone detection system based on Elecrow HMI , 3 x 2.4GHz nRF24L01 modules, ESP32Wroom
This document details the development and capabilities of a prototype drone proximity alert system, engineered as a POC to demonstrate the feasibility of rapid development for this technology.
The system is designed for cost-effective mass production and broad area coverage, prioritizing the utilization of readily available components and an efficient design.
Built in just a week using readily available parts, this prototype drone detection system includes an intuitive HMI for easy setup and monitoring. Powered by an ESP32 microcontroller, it features nRF24L01+ transceivers and directional antennas to achieve a detection range of over 200 meters.
This prototype showcases a fast-development approach for a drone proximity alert system. It is designed for cost-effective mass production and extensive area coverage, using readily available components and a straightforward design
Each system utilizes the following components (multiple systems can be deployed):
HMI: 5" Elecrow HMI display (only one required)
RF Module: Three or more Nordic Semiconductor nRF24L01+ 2.4GHz transceivers
Microcontroller: ESP32 for managing RF modules and HMI communication
Antennas: Directional (YAGI) and omnidirectional antennas
Power Source: External battery
Additional Materials: Case, RF cables , Decoupling Capacitors , Voltage Regulator
The system uses the nRF24L01+ transceiver module, which features a built-in power amplifier and offers 125 selectable channels within the globally license-free 2.4GHz ISM band
This drone detection system leverages signal strength variations to identify
approaching drones. The system employs a combination of directional and
omnidirectional antennas to enhance detection accuracy and minimize false alarms.
The integration of three nRF24 units provides operational flexibility, enabling customized
configurations for range, channel selection, and scanning speed optimization.
Initial drone flight tests were performed using a basic nRF24L01+ setup with various antennas to study signal behavior and optimize reception quality.
Based on these test results, the hardware was configured with three nRF24L01+ receivers and YAGI directional antennas to improve signal sensitivity and adding a direction-finding capabilities.
Code was developed for the ESP32 to control the nRF24L01+ receivers. The HMI was designed with a user-friendly interface, providing flexibility and options for future feature enhancements, with a focus on efficient field operation and clear alert displays.
The system software is developed using Arduino IDE for the ESP32, managing control of the three nRF24L01+ modules, I2C communication for the OLED display, and serial connectivity to the HMI. The HMI interface, created with the LVGL library in Visual Studio, enables rapid GUI development, providing an easy-to-use interface and clear visual feedback during field operations and experiments.
Individual control and parameter setting for each nRF24L01+ receiver.
Selection and monitoring of specific channels of interest within the 2.4GHz band.
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A single HMI unit is designed to connect to multiple drone detection systems, reducing overall costs.
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Future Networked Deployment: Plans include connecting multiple systems within a closed network for improved detection capabilities and operational efficiency.
The prototype was developed within a week, demonstrating the efficiency of the chosen approach.
Adding more channels with dedicated directional antennas can significantly improve direction-finding accuracy.
Using a metallic enclosure and positioning antennas up to 2 meters away from the unit significantly improves system sensitivity and resilience to environmental noise.
- Full Spectrum Scanning: Scan all available frequencies using all nRF modules
- Selective Channel Monitoring: Monitor specific channels or a defined frequency range
- Individual nRF Configuration: Configure different scanning frequencies
- Dedicated channel for each nRF24L01+ receiver (up to 3 in total)
- Individual alerts can be configured for each nRF module
Successful field tests were conducted with a drone flying at altitudes between 15 and 25 meters. The system, equipped with two directional antennas and an omnidirectional antenna for ambient noise reference, detected the drone at distances over 200 meters