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Version: 2.0 (Legacy)

Bandwidth Switching

Dynamic bandwidth adjustment for optimal OpenHD performance across different flight phases.

Overview​

Bandwidth switching enables:

  • Adaptive Quality: Adjust video quality based on range
  • Flight Phase Optimization: Different settings for different flight phases
  • Signal Strength Response: Automatic adjustment based on signal quality
  • Manual Control: Pilot-controlled bandwidth changes

Bandwidth Modes​

High Bandwidth Mode​

  • Close Range: Optimal for short-range operations
  • High Quality: Maximum video resolution and bitrate
  • Low Latency: Minimal compression delays
  • Full Features: All telemetry and control functions

Medium Bandwidth Mode​

  • Medium Range: Balanced performance and range
  • Moderate Quality: Reduced resolution or bitrate
  • Stable Connection: Reliable link maintenance
  • Essential Features: Core functions maintained

Low Bandwidth Mode​

  • Long Range: Maximum range capability
  • Reduced Quality: Lower resolution and bitrate
  • High Reliability: Error correction prioritized
  • Critical Functions: Essential telemetry only

Automatic Switching​

Signal-Based Switching​

  • RSSI Thresholds: Switch based on signal strength
  • Packet Loss Monitoring: Respond to connection quality
  • Link Quality Assessment: Multiple signal metrics
  • Hysteresis: Prevent rapid switching between modes

Distance-Based Switching​

  • GPS Distance: Switch based on distance from home
  • Altitude Switching: Adjust for altitude changes
  • Flight Path: Predetermined switching points
  • Zone Configuration: Define switching zones

Manual Control​

RC Channel Assignment​

  • Switch Assignment: Assign bandwidth mode to RC switch
  • Multi-position Switch: 3-position switch for 3 modes
  • Smooth Transitions: Gradual bandwidth changes
  • Status Indication: Visual feedback of current mode

Ground Control Interface​

  • Software Control: Change modes via ground control software
  • Real-time Adjustment: Immediate bandwidth changes
  • Profile Selection: Pre-configured bandwidth profiles
  • Emergency Override: Quick switch to safe mode

Configuration Parameters​

Video Settings​

  • Resolution Scaling: Automatic resolution adjustment
  • Bitrate Control: Dynamic bitrate modification
  • Frame Rate: Adjust FPS for bandwidth
  • Compression: Variable compression levels

Protocol Settings​

  • FEC Levels: Adjust error correction
  • Packet Size: Optimize packet sizes
  • Retry Logic: Configure retransmission
  • Priority Systems: Prioritize critical data

Implementation​

Switching Logic​

High Bandwidth (< 500m, RSSI > -50dBm):
- Resolution: 1920x1080
- Bitrate: 10 Mbps
- FEC: Low
- Latency: Minimal

Medium Bandwidth (500m-2km, RSSI -50 to -65dBm):
- Resolution: 1280x720
- Bitrate: 5 Mbps  
- FEC: Medium
- Latency: Moderate

Low Bandwidth (> 2km, RSSI < -65dBm):
- Resolution: 854x480
- Bitrate: 2 Mbps
- FEC: High
- Latency: Higher

Transition Behavior​

  • Gradual Changes: Smooth transitions between modes
  • Buffering: Maintain video during switches
  • Status Updates: Inform pilot of mode changes
  • Fallback: Automatic fallback to safe mode

Performance Optimization​

Latency Considerations​

  • Switching Delay: Minimize mode change time
  • Processing Impact: Account for processing overhead
  • Buffer Management: Optimize video buffers
  • Prediction: Anticipate bandwidth needs

Quality Management​

  • Adaptive Encoding: Dynamic encoding parameter adjustment
  • Quality Metrics: Monitor video quality metrics
  • User Preferences: Prioritize pilot preferences
  • Mission Requirements: Adjust for mission needs

Use Cases​

Long Range Missions​

  • Extended Range: Maximize operational range
  • Fuel Efficiency: Optimize for flight duration
  • Safety Margins: Maintain reliable connection
  • Emergency Return: Ensure return link capability

High-Quality Recording​

  • Close Range Operations: Maximum quality when close
  • Cinematic Work: High quality for video production
  • Inspection Tasks: Detail-oriented applications
  • Documentation: High-quality documentation needs

Mixed Operations​

  • Takeoff/Landing: High quality for precision operations
  • Transit: Medium quality for travel phases
  • Destination: Adjust for operational requirements
  • Return: Ensure safe return capability

Monitoring and Diagnostics​

Performance Metrics​

  • Link Quality: Monitor connection statistics
  • Video Metrics: Track video quality parameters
  • Switching History: Log bandwidth changes
  • Performance Analysis: Post-flight analysis

Status Display​

  • Current Mode: Display active bandwidth mode
  • Signal Strength: Real-time signal monitoring
  • Quality Indicators: Video quality metrics
  • Switching Triggers: Show switching reasons

Troubleshooting​

Switching Issues​

  • Erratic Switching: Adjust threshold settings
  • Failed Switches: Check system resources
  • Poor Transitions: Optimize switching logic
  • Status Confusion: Improve status indicators

Performance Problems​

  • Inadequate Switching: Review switching criteria
  • Quality Issues: Adjust bandwidth allocation
  • Latency Problems: Optimize processing pipeline
  • Range Limitations: Review power and antenna setup

:::info Customization Bandwidth switching parameters should be customized for specific aircraft, missions, and operating environments. :::

:::warning Testing Required Always test bandwidth switching thoroughly in safe conditions before relying on it for important missions. :::

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