WiMAX Signal Interference (DFS)

Some Vfast broadband services use licensed wireless technology (WiMAX), particularly in rural areas and holiday parks. This technology shares radio frequencies with important services such as weather radar and aviation systems.

When these priority signals are detected, your broadband connection may briefly change how it operates. This is normal and required by regulation.

What is DFS?

DFS (Dynamic Frequency Selection) is an automatic safety feature built into regulated wireless networks.

It works by:

• Detecting priority radio signals (such as radar)
• Automatically changing frequency to avoid interference
• Keeping essential services protected

This behaviour is required by regulation and is part of normal network operation.

What you might notice

When DFS occurs, you may experience:

• A short loss of connection
  
• Slower speeds than usual
  
• Brief instability or dropouts

In most cases, the connection recovers on its own within a short time.

Why Speeds Can Stay Reduced

After a frequency change:

• The new channel may not be as strong for your location
• Signal quality may be lower
• Speeds may remain reduced until conditions improve

This does not mean your router or equipment is faulty.

What You Should Do

If your service recovers quickly, no action is needed.

If problems continue for an extended period (for example, repeated dropouts or consistently slow speeds):

Contact the Service Desk so we can:

• Check the transmitter serving your area
• Review current operating channels
• Make adjustments to improve stability where possible

Reporting ongoing issues helps us optimise performance for your area.

Should I Reset My Router?

Do not reset your router unless the Service Desk tells you to.

Resetting removes important settings and can make faults harder to diagnose.

Instead, if performance seems poor:

• Power the router off and back on once
  
• Follow: Troubleshooting Slow Broadband Speeds
  
• Follow: Troubleshoot Dropouts

This helps rule out Wi-Fi or internal issues before we investigate the wireless network.

Is DFS Common?

DFS events are:

• Typically uncommon
• Usually short-lived
• A normal part of licensed wireless operation

If a transmitter experiences repeated DFS events, our engineering team will investigate and make adjustments to improve reliability.

Need help?

If your connection does not recover or remains unstable after completing the relevant checks, contact the Service Desk.

See:

• How to Contact the Vfast Service Desk
  
• Support Availability & Response Times

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• Troubleshooting Slow Broadband
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