Some Lobaro devices do support mobile connections like NB-IoT or LTE-Cat-M1. This page contains background information and technical details related to the mobile connections.
Content
LTE Signal strength
The signal strength of the LTE-M1 or NB-IoT network can be derived from the RSRP and RSRQ dimensionless values.
- RSRP - 140 = dBm
- RSRQ / 2 - 19.5 = dB
| Coverage | LTE RSRP | LTERSRP (dBm) | RSRQ | RSRQ (dB) |
|---|---|---|---|---|
Average power received | Average power received (dBm) | Average receive quality | Average receive quality (dB) | |
| Excellent (4/4) | 80 - 97 | -60 to -44 | 28 - 34 | -5.5 to -3 |
| Good (3/4) | 60 - 79 | -80 to -61 | 21 - 27 | -9 to -6 |
| Mid Cell (2/4) | 40 - 59 | -100 to -81 | 14 - 20 | -12.5 to -9.5 |
| Cell Edge (1/4) | 20 - 39 | -120 to -101 | 7 - 13 | -16 to -13 |
| Unstable (0/4) | 0 - 20 | -140 to -121 | 0 - 7 | -19.5 to -16.5 |
The actual value of your devices connection statistics is shown in the Lobaro platform under "Device Properties".
For "unstable" network coverage Lobaro can't guarantee the correct function of the cellular uplinks and battery lifes under all conditions. Please consider a different location for the particular device.
Modem specifics (nRF9160)
Today Lobaro is using the Nordic nRF9160 in most of it's products. Beside that app the Modem Firmware from Nordic is running on a separate core.
Known issues
Modem Firmware < 1.3.0 does not support LTE-M and NB-IoT at the same time (relevant until 10/2022)
When enabling both LTE-M and NB-IoT in a Lobaro Firmware that runs with Modem Firmware < 1.3.0 the Modem can not do a fallback to LTE-M when NB-IoT is not available and thus the firmware only uses NB-IoT in that case.
With Modem Firmware >= 1.3.0 a proper fallback is implemented.
nrf9160 SICA vs. SIBA (no LTE-M) (relevant until ~12/2021)
The nrf9160 SIBA only supports NB-IoT but not LTE-M. Since late 2021 Lobaro only uses the nrf9160 SICA which supports both NB-IoT and LTE-M.