sky_rfi

Architecture Overview

The CASM RFI Sky Monitor consists of several key components:

Components

Frontend (Web Interface)

• Interactive 2D and 3D visualizations
• Real-time data updates via polling
• Responsive design for multiple devices

Backend (Flask API)

• REST endpoints for position data
• Historical snapshot access
• Real-time live data streaming

Data Processing

• Satellite position calculations using Skyfield
• Aircraft tracking via OpenSky Network
• Horizon visibility masking
• 3D coordinate transformations

Data Storage

• SQLite database for snapshots
• Cache files for TLE data and horizon profiles
• GeoJSON data for map overlays

Scheduling

• Background thread for periodic TLE updates
• Aircraft position refresh cycles
• Automatic snapshot saving

Data Flow

1. TLE Acquisition: Download satellite data from CelesTrak
2. Position Calculation: Calculate positions relative to observer
3. Visibility Determination: Check if objects are above horizon
4. Snapshot Storage: Periodically save visible objects to database
5. Visualization: Display on interactive web interface
6. API Access: Expose data via REST endpoints

Configuration

All settings are configured via config.yaml:

• Observatory Location: Latitude, longitude, altitude
• Horizon Profile: Panorama ID from HeyWhatsThat
• API Credentials: OpenSky Network credentials (optional)
• Cache Locations: TLE, horizon, and geospatial data paths
• Update Intervals: Timing for data refreshes
• Server Settings: Host, port, worker configuration

Visibility Calculation

An object is visible if:

1. Altitude Check: Above the horizon (accounting for terrain)
2. Aircraft Distance Check: Closer than horizon obstruction distance (aircraft only)

The horizon profile is interpolated at the object’s azimuth to determine the minimum altitude for visibility.

Technologies

• Backend: Flask, Skyfield, NumPy
• Frontend: Plotly, JavaScript
• Data: SQLite, YAML, GeoJSON
• APIs: OpenSky Network, CelesTrak, HeyWhatsThat