Propagation Maps

Propagation Maps Guide

VOACAP-Style Coverage Maps with Maidenhead Grid Overlay

Overview

The Propagation Maps feature provides VOACAP-compatible signal strength and reliability predictions visualized on an interactive map with Maidenhead grid square alignment.

What You Get:

Reliability (REL) Maps - Circuit reliability percentage (0-100%)
Signal Strength (SDBW) Maps - Signal-to-noise ratio in dB
Maidenhead Grid Alignment - Perfect for amateur radio operators
Interactive Display - Click grid squares for detailed predictions
Mode-Specific Predictions - WSPR, FT8, CW, SSB presets
Space-Efficient Design - Fullscreen map interface

Features

Two Map Types

1. Reliability (REL) Maps Shows circuit reliability percentage based on signal fading statistics and required SNR threshold.

Color Scale:

🔴 Red (90-100%): Excellent propagation
🟠 Orange (70-90%): Good propagation
🟡 Yellow (50-70%): Fair propagation
🟢 Green (30-50%): Marginal propagation
🔵 Blue (10-30%): Poor propagation
⚪ Gray (0-10%): Unlikely propagation

2. Signal Strength (SDBW) Maps Shows signal-to-noise ratio in decibels.

Color Scale:

🔴 Red (>40 dB): S9+ signals
🟠 Orange (30-40 dB): S9 signals
🟡 Yellow (20-30 dB): S7 signals
🟢 Green (10-20 dB): S5 signals
🔵 Blue (0-10 dB): S3 signals
⚪ Gray (<0 dB): Weak signals

Mode Presets

Automatic configuration for common amateur radio modes:

Mode	Bandwidth	Required SNR	VOACAP Match
WSPR	6 Hz	-28 dB	3 dB/Hz ✓
FT8	50 Hz	-21 dB	19 dB/Hz ✓
CW	500 Hz	+6 dB	13 dB/Hz ✓
SSB	2700 Hz	+10 dB	38 dB/Hz ✓

These match VOACAP's bandwidth specifications exactly for accurate predictions.

Quick Start

1. Generate Map Data

cd Dashboard
python generate_propagation_maps.py

This creates map files in Dashboard/propagation_maps/:

map_20m_SSB_1800Z.json
map_20m_FT8_1800Z.json
map_40m_FT8_0000Z.json
map_15m_FT8_1800Z.json

First Generation Time: ~5-10 minutes per map (25,000+ grid points)

2. View Maps

Option A: Via Dashboard Server

cd Dashboard
python server.py

Then open: http://localhost:8000/propagation_maps.html

Option B: Direct File Access Open Dashboard/propagation_maps.html directly in your browser.

3. Interact with Maps

Controls:

Band Selection: 40m, 20m, 17m, 15m, 10m
Mode Selection: WSPR, FT8, CW, SSB
Display Toggle: Reliability ↔ Signal Strength
Time Selection: Hourly UTC (0-23)
Refresh: Generate new predictions

Click any grid square for detailed popup:

Grid: FN74
Distance: 4,689 km
SNR: 26.2 dB
Reliability: 82.9%
Mode: 2F2 (2 hops)

Using Programmatically

Generate Custom Maps

from Dashboard.generate_propagation_maps import generate_propagation_map

# Your station
TX_LAT = 44.374
TX_LON = -64.300

# Generate map
map_data = generate_propagation_map(
    tx_lat=TX_LAT,
    tx_lon=TX_LON,
    frequency=14.074,      # 20m FT8
    mode='FT8',
    utc_hour=18,
    month=11,
    ssn=77,
    tx_power=80.0,
    map_range_deg=60.0,    # ±60° coverage
    resolution='medium'     # 2° x 1° grid squares
)

# Access predictions
for pred in map_data['predictions']:
    print(f"{pred['grid']}: SNR={pred['snr_db']:.1f} dB, "
          f"REL={pred['reliability']:.1f}%")

Apply Mode Presets

from src.dvoacap.prediction_engine import PredictionEngine
from Dashboard.mode_presets import apply_mode_preset

engine = PredictionEngine()

# Automatically configure for FT8
apply_mode_preset(engine, 'FT8')
# Now engine.params.bandwidth_hz = 50
# And engine.params.required_snr = -21

# Or manually set
engine.params.bandwidth_hz = 2700  # SSB
engine.params.required_snr = 10    # 10 dB SNR

Map Data Format

{
  "metadata": {
    "generated": "2025-11-17T23:30:00Z",
    "tx_location": {"lat": 44.374, "lon": -64.300},
    "frequency_mhz": 14.074,
    "mode": "FT8",
    "ssn": 77,
    "bandwidth_hz": 50,
    "required_snr": -21,
    "grid_count": 25652,
    "successful_predictions": 24891
  },
  "statistics": {
    "snr": {
      "min": -5.2,
      "max": 45.3,
      "mean": 28.7,
      "median": 30.1
    },
    "reliability": {
      "min": 12.3,
      "max": 98.7,
      "mean": 76.2,
      "median": 81.5
    }
  },
  "predictions": [
    {
      "grid": "FN74",
      "lat": 44.5,
      "lon": -64.0,
      "distance_km": 45.2,
      "snr_db": 42.1,
      "reliability": 95.3,
      "signal_dbw": -68.2,
      "loss_db": 142.5,
      "mode": "1F2",
      "hops": 1
    }
  ]
}

Performance

Map Generation

Resolution	Grid Points	Generation Time	File Size
Coarse (field)	~1,000	1-2 min	50-100 KB
Medium (square)	~25,000	5-10 min	200-500 KB
Fine (subsquare)	~250,000	50-100 min	2-5 MB

Recommendation: Use medium resolution for most applications.

Map Display

Loading Time: <1 second
Rendering: Instant with Leaflet
Memory Usage: ~10 MB per map
Browser Support: All modern browsers

Advanced Configuration

Custom Grid Resolution

# Coarse: 10° x 5° field-level squares
map_data = generate_propagation_map(..., resolution='coarse')

# Medium: 2° x 1° square-level (default)
map_data = generate_propagation_map(..., resolution='medium')

# Fine: 5' x 2.5' subsquare-level
map_data = generate_propagation_map(..., resolution='fine')

Custom Map Range

# Local coverage (±30°)
map_data = generate_propagation_map(..., map_range_deg=30.0)

# Continental coverage (±60°)
map_data = generate_propagation_map(..., map_range_deg=60.0)

# Global coverage (±90°)
map_data = generate_propagation_map(..., map_range_deg=90.0)

Batch Generation

Generate maps for multiple scenarios:

bands = [(7.074, '40m'), (14.074, '20m'), (21.074, '15m')]
modes = ['WSPR', 'FT8', 'CW', 'SSB']
hours = [0, 6, 12, 18]

for (freq, band), mode, hour in itertools.product(bands, modes, hours):
    map_data = generate_propagation_map(
        tx_lat=TX_LAT, tx_lon=TX_LON,
        frequency=freq, mode=mode, utc_hour=hour,
        month=MONTH, ssn=SSN
    )
    # Save or process map_data

Comparison to VOACAP

Feature	VOACAP	DVOACAP-Python	Status
REL Maps	✅ Static PNG	✅ Interactive	Enhanced
SDBW Maps	✅ Static PNG	✅ Interactive	Enhanced
Maidenhead Grid	❌ Not aligned	✅ Perfect alignment	New
Mode Presets	❌ Manual entry	✅ Auto-config	New
Bandwidth Parameter	✅ Yes	✅ Yes	Fixed
Click for Details	❌ No	✅ Yes	New
Export Format	PDF/PNG	JSON + HTML	Enhanced

Integration with Dashboard

Add to Main Dashboard

Option 1: Navigation Link

<a href="propagation_maps.html" class="nav-link">
    📊 Propagation Maps
</a>

Option 2: Embedded Tab

<div class="tab-content" id="maps-tab">
    <iframe src="propagation_maps.html"
            style="width:100%;height:100%;border:none;">
    </iframe>
</div>

Option 3: Flask Route

@app.route('/maps')
def maps_page():
    return send_from_directory('Dashboard', 'propagation_maps.html')

Troubleshooting

Map Data Not Found

Error: Map data not found: map_20m_SSB_1800Z.json

Solution: Generate maps first:

cd Dashboard
python generate_propagation_maps.py

Slow Map Generation

Problem: Takes >10 minutes to generate

Solutions:

Use coarse resolution for wide areas
Reduce map_range_deg (e.g., 30° instead of 60°)
Run overnight for large batches
Cache generated maps (reuse for same conditions)

High Memory Usage

Problem: Browser uses >500 MB RAM

Solutions:

Close unused tabs
Reduce map_range_deg
Use coarse/medium resolution
Restart browser periodically

Future Enhancements

Planned features:

Real-time Generation - API endpoint for on-demand maps
Animation - 24-hour time-lapse playback
Path Overlay - Show specific DX paths on map
Contour Lines - Add MUF/FOT/LUF contours
3D Visualization - Height-coded reliability surface
Export - Save maps as PNG/PDF
Compare Mode - Side-by-side WSPR vs SSB

References

VOACAP Online: voacap.com
Maidenhead System: Wikipedia
DVOACAP Validation: See VOACAP_VALIDATION_FINDINGS.md
Implementation Details: See Dashboard/PROPAGATION_MAPS_README.md

Credits

VOACAP: Original propagation model by NTIA/ITS
DVOACAP: Pascal implementation by Alex Shovkoplyas (VE3NEA)
DVOACAP-Python: Python port with map enhancements
Leaflet: Interactive mapping library

Last Updated: 2025-11-18 Status: Production Ready Tested With: 20m/40m/15m on SSB/FT8/CW/WSPR modes

Propagation Maps

Propagation Maps Guide

Overview

Features

Two Map Types

Mode Presets

Quick Start

1. Generate Map Data

2. View Maps

3. Interact with Maps

Using Programmatically

Generate Custom Maps

Apply Mode Presets

Map Data Format

Performance

Map Generation

Map Display

Advanced Configuration

Custom Grid Resolution

Custom Map Range

Batch Generation

Comparison to VOACAP

Integration with Dashboard

Add to Main Dashboard

Troubleshooting

Map Data Not Found

Slow Map Generation

High Memory Usage

Future Enhancements

References

Credits

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