Wireless RF Monitoring

ESP32 Multi nRF24 RF Scanner

A multi-radio 2.4GHz RF monitoring project using an ESP32 to interface with multiple nRF24L01+PA+LNA modules over dedicated SPI buses.

ESP32 Dual SPI buses

nRF24 2.4GHz scan

Modes Random/Sweep

Project Overview

This project demonstrates a multi-radio wireless scanning setup using an ESP32 Development Board and multiple nRF24L01+PA+LNA modules. The ESP32 coordinates hardware communication across different radio modules by utilizing its independent HSPI and VSPI bus interfaces.

Each nRF24 module monitors different 2.4GHz channels, making this setup an excellent tool for RF experimentation, channel activity analysis, and learning advanced multi-SPI hardware integration on the ESP32 platform.

View GitHub Repo

Components Integrated

nRF24L01+PA+LNA Long-range 2.4GHz radio transceiver modules with external antenna support.

SPI Bus Interfaces Hardware-level HSPI/VSPI implementation for high-speed multi-module communication.

Project Resources

ESP8266 Firmware Motion detection firmware featuring ultrasonic sensing, visitor counting, LED indication, NTP time synchronization, and Twilio WhatsApp alert integration.

Hardware Connections Complete wiring guide for NodeMCU ESP8266, HC-SR04 Ultrasonic Sensor, LED indicator, power connections and GPIO mapping.

Pin Configuration

Component	NodeMCU Pin
HC-SR04 TRIG	D1 (GPIO5)
HC-SR04 ECHO	D2 (GPIO4)
LED Indicator	D5 (GPIO14)
VCC	VIN
GND	GND

System Workflow

Google Assistant

ESP RainMaker

ESP32

Relay Module

Home Appliances

Project Source Codes

1. ESP32 RF Scanner Firmware

Controls dual SPI buses, multiple nRF24L01 modules, channel scanning, and RF monitoring modes.

Download ESP32 Code

View ESP32 Source Code



#include <SPI.h>
#include <RF24.h>

/*
 ESP32 Multi nRF24 RF Scanner
 Dual SPI Bus Implementation
 Channel Sweep & Random Scan
*/

/* Complete source available in download */

2. Wiring Diagram & Pin Mapping

Complete ESP32 pin assignments, HSPI and VSPI connections, CE and CSN wiring details.

Download Wiring Diagram

View Wiring Information



HSPI Bus
SCK  -> GPIO14
MISO -> GPIO12
MOSI -> GPIO13

VSPI Bus
SCK  -> GPIO18
MISO -> GPIO19
MOSI -> GPIO23

Radio 1
CE   -> GPIO26
CSN  -> GPIO15

Radio 2
CE   -> GPIO25
CSN  -> GPIO5

3. Hardware Documentation

Component specifications, power requirements, antenna configuration, and assembly instructions.

Download Hardware Guide

View Hardware Details



Included Resources:

• ESP32 Development Board
• nRF24L01+PA+LNA Modules
• Power Supply Design
• External Antenna Setup
• RF Channel Configuration

4. User Manual & Setup Guide

Step-by-step setup instructions, scanner operation guide, troubleshooting tips, and deployment notes.

Download User Manual

View Setup Guide



Setup Steps:

1. Connect both nRF24 modules
2. Verify SPI wiring
3. Upload firmware
4. Open Serial Monitor
5. Select Sweep or Random Mode
6. Monitor RF Channel Activity

Technologies Used

ESP32 ESP RainMaker Google Assistant Arduino IDE Bluetooth Provisioning OTA Updates EEPROM AceButton Wi-Fi Embedded C++

Note: We are currently developing an online flashing tool to simplify your firmware deployment. Check back soon for seamless browser-based uploads!