PROJECT OVERVIEW
Mission Statement
ILSA (Interference Localization and Spectrum Analysis) is a multi-processor embedded system for real-time non-Wi-Fi interference detection and characterization in the 2.4 GHz ISM band. The system identifies interference sources and provides directional information using Angle of Arrival (AoA) techniques.
The 2.4 GHz ISM band is heavily utilized by Wi-Fi networks, Bluetooth devices, and various other wireless technologies. However, non-Wi-Fi interference sources such as microwave ovens, cordless phones, and other RF devices can significantly degrade network performance.
Project Goals
Course Learning Objectives
- Inter-Processor Communication: A7 ↔ M4 via OpenAMP/RPMsg
- Real-Time Embedded Task: M4 handles time-critical ADC sampling
- Production Mode Deployment: M4 firmware loaded via Linux remoteproc
- System Design: Complete documentation and presentation
Application Objectives
- Detect interference on 2.4 GHz channels (1-14)
- Distinguish Wi-Fi from interference
- Locate interference source direction using dual-antenna AoA
- Real-time operation with minimal latency
System Architecture
Cortex-A7 (Linux)
- • Wi-Fi network scanning
- • User interface and control
- • Interference calculation
- • Angle of Arrival computation
- • RPMsg client communication
Cortex-M4 (Bare-Metal)
- • Real-time dual-antenna ADC sampling
- • RF receiver control and channel tuning
- • RF energy measurement across channels
- • RPMsg server communication
Communication
OpenAMP/RPMsg via shared memory (/dev/rpmsg0)
Operating Modes
Analyze Mode
Scans all 2.4 GHz channels (1-14), measures RF energy, compares with Wi-Fi RSSI, and flags channels with interference >10 dB above Wi-Fi.
Locate Mode
Focuses on specific channel, samples dual antennas simultaneously, calculates Angle of Arrival from RSSI difference, and displays bearing (-90° to +90°).