Check WiFi Channel Utilization¶
Available in v0.1.1 -- The WiFi skill group (
unifi wifi) is planned for Phase 2. This workflow documents the intended behavior. Phase 1 provides partial coverage through the health and clients tools described below.
Intent¶
"I want to see which channels are congested across all APs."
Prerequisites¶
- Plugin:
unifiv0.1.1 or later (for full WiFi analysis) - API privileges: Read-only access to the Local Gateway API
- Environment variables:
UNIFI_LOCAL_HOSTandUNIFI_LOCAL_KEYmust be configured
For Phase 1 (v0.1.0), the following partial approach is available using existing tools.
Context¶
Run this workflow when wireless clients report slow speeds, when you are planning AP placement, or after adding new APs to check for co-channel interference. Channel congestion is one of the most common causes of poor WiFi performance, especially in dense environments.
This workflow is entirely read-only. It uses passive data only -- the plugin never triggers an active RF scan.
This workflow does not cover WiFi optimization recommendations -- see unifi optimize (Phase 2) for channel and power adjustment suggestions.
Commands¶
Phase 1 (v0.1.0): Partial Coverage¶
In Phase 1, you can gather channel-related information from the device and client data:
Step 1: Scan for AP radio information¶
The scan output includes device details. For APs, the fixture data shows radio configuration including channel assignments. You can also ask for specific device details:
The device detail includes radio_table with channel, bandwidth, and transmit power for each radio band, and radio_table_stats with channel utilization, self-TX/RX, and client satisfaction per radio.
Step 2: Check client signal quality across APs¶
Review the Signal column in the client inventory. Clients with Fair or Poor signal on a given AP may benefit from a channel change or additional AP coverage.
Phase 2 (v0.1.1): Full WiFi Analysis¶
When the WiFi skill group is available, the full workflow will use the unifi wifi command:
Step 1: Run WiFi analysis¶
This will call:
- unifi__wifi__get_aps -- list all APs with channel assignments
- unifi__wifi__get_channel_utilization -- per-AP channel utilization percentages
- unifi__wifi__get_rf_scan -- cached RF scan showing neighboring SSIDs
Step 2: Review channel utilization (expected output)¶
EmberAI:
## WiFi Channel Analysis
### 2.4 GHz Band
| AP | Channel | Utilization | Interference | Clients | Satisfaction |
|------------------|---------|-------------|--------------|---------|--------------|
| Office-AP-Main | 6 | 32% | 12% | 18 | 92 |
| Office-AP-Upstrs | 1 | 15% | 5% | 8 | 97 |
### 5 GHz Band
| AP | Channel | Utilization | Interference | Clients | Satisfaction |
|------------------|---------|-------------|--------------|---------|--------------|
| Office-AP-Main | 44 | 18% | 3% | 17 | 98 |
| Office-AP-Upstrs | 149 | 12% | 2% | 12 | 99 |
### Neighboring SSIDs (from RF scan)
| SSID | Channel | Band | RSSI | Security |
|------------------|---------|-------|------|----------|
| Neighbor-Net | 6 | 2.4 | -72 | WPA3 |
| DIRECT-printer | 6 | 2.4 | -68 | WPA2 |
| ApartmentWiFi | 1 | 2.4 | -80 | WPA2 |
What to Look For¶
Channel utilization: - < 30% -- healthy, no action needed - 30-60% -- moderate congestion; acceptable if client satisfaction is high - > 60% -- heavy congestion; consider changing channels or reducing AP count on that channel
Interference percentage: - High interference with low self-TX/RX means most channel usage is from external sources (neighbors, non-WiFi devices). Changing channels may help. - High self-TX/RX with low interference means your own network is the primary channel user. This is expected with many clients.
Client satisfaction: - Per-AP satisfaction below 80 combined with high utilization is a strong signal to investigate channel changes.
Neighboring SSIDs: - Multiple strong neighbors (RSSI > -70) on the same channel as your AP cause co-channel interference. - On 2.4 GHz, only channels 1, 6, and 11 are non-overlapping. If all three are heavily occupied, consider steering clients to 5 GHz.
Next Steps¶
- Locate a Client -- diagnose a specific client with poor signal
- Daily Health Check -- check overall AP health
unifi optimize(Phase 2) -- get channel and power adjustment recommendations
Troubleshooting¶
| Symptom | Likely Cause | Fix |
|---|---|---|
| Channel utilization shows 0% | Radio stats not populated | Some AP models require a recent client association to populate radio stats |
| RF scan returns empty | No cached scan data available | The controller must have performed a background scan; this happens automatically on most AP models |
| Only 2.4 GHz data available | AP does not have 5 GHz radio or it is disabled | Check AP model capabilities and radio settings in the controller |
| Satisfaction score is "None" | AP model does not report satisfaction metrics | Older AP models may not expose this field |