Understanding signal strength
Your Invisible Systems devices communicate wirelessly. The strength and quality of that wireless signal affects how reliably your devices can send data. This guide explains what the signal readings in your diagnostics mean and what you can do if signal is poor.
Signal Readings Explained
RSSI — Signal Strength
RSSI (Received Signal Strength Indicator) measures how strong the wireless signal is. The less negative the number, the stronger the signal.
| RSSI Value | Signal Strength | What to Expect |
|---|---|---|
| Above -80 dBm | Excellent | Very reliable connection |
| -80 to -100 dBm | Acceptable | Generally reliable — monitor if intermittent issues arise |
| Below -100 dBm | Poor | Device may go offline or miss transmissions — action recommended |
SNR Margin — Signal Quality
SNR Margin measures how cleanly the signal can be heard above background radio noise. A higher number means the signal is easier to decode reliably.
| SNR Margin | Signal Quality |
|---|---|
| Above 10 dB | Good — reliable connection expected |
| 6–10 dB | Acceptable — generally reliable |
| 3–6 dB | Marginal — may experience occasional missed readings |
| Below 3 dB or negative | Poor — device likely to go offline or miss data |
Why Signal Matters
Our devices are designed to work at long range with low power. They can maintain a connection even at surprisingly low signal levels. However, when signal drops below acceptable levels:
- Readings may not reach the platform, causing gaps in data.
- The device may appear online but miss transmissions.
- In severe cases, the device will appear fully offline.
How to Improve Signal
If signal is poor, try the following in order:
- Check whether the device has been moved since installation — signal can vary significantly by location. Moving it back to the original position may resolve the issue.
- Reposition the device to a location with a clearer line of sight to the gateway. Avoid placing devices behind large metal objects, inside metal enclosures, or next to heavy electrical equipment.
- Check whether anything has changed near the device — new equipment, structural changes, or new electrical devices in the area can all affect signal.
- If repositioning the device is not possible or does not help, contact support. It may be that a gateway needs to be added or repositioned to improve coverage.
LoRaWAN signals can pass through walls and floors, but thick concrete, metal structures, and certain building materials significantly reduce range. Outdoor or high-mounted gateways generally provide the best coverage.
Where to Find Signal Readings
- Log in to Live and navigate to the relevant site.
- Open the device diagnostics for the sensor you want to check.
- Look for the RSSI and SNR values in the diagnostics panel.
If you are unsure where to find this, contact support and the team can check signal levels remotely.