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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.

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LTE Signal strength

The signal strength of the LTE-M1 or NB-IoT network can be derived from the RSRP and RSRQ dimensionless values.

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The actual value of your devices connection statistics is shown in the Lobaro platform under "Device Properties".

For "unstable" network coverage Lobaro can 't not guarantee the correct function of the cellular uplinks and battery lifes runtimes under all conditions. Please consider a different location for the particular device.

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Source: https://infocenter.nordicsemi.com/index.jsp?topic=%2Fref_at_commands%2FREF%2Fat_commands%2Fmob_termination_ctrl_status%2Fproc_cesq_set.html

Geo Location Lookup

There are multiple ways to trace where a mobile device is.

In General the following information is required and transmitted in the device status packets:

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• TAC → lac (dezimal), 0xcb20 = 52000
  • Tracking Area Code (TAC) sometimes called Location Area Code (LAC)
• CI → cid (dezimal), 0x299A605 = 43623941
  • Cell ID (CID / CID)

Here are some resources to use:

LTE network error codes

Newer firmware of Lobaro products report potential ESM (EPS Session Management) and EMM (EPS Mobility Management) errors in their status uploads.

EMM Error codes

Source: ETSI TS 124 301 V14.5.0 - Table 9.9.3.9.1: ESM cause information element

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E.g.: +CNEC_EMM: 19 is error code 19 which is 0b10011 which corresponds to ESM failure (see table below)

ESM Error codes

Source: ETSI TS 124 301 V14.5.0 - Table 9.9.4.4.1: ESM cause information element

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CNEC_ESM: 27,0 is error code 27 with cid 0, and 27 is binary 1b11011 which corresponds to Missing or unknown APN

NB-IoT network coverage

Please see: https://iotcreators.com/network/?#G

For testing the coverage you can use our hardware with our USB Config Adapter and the Lobaro Maintenance Tool to observe the log during connection.

Or test yourself using a professional 3rd party network tester e.g. from ENQT.

Modem specifics (nRF9160)

Today Lobaro is using the Nordic nRF9160 in most of it's products. Beside that Lobaro Firmware the Modem Firmware from Nordic is running on a separate core.

Modem Parameter

Integrated Circuit Card Identifier (ICCID)

Please see: https://help.1nce.com/dev-hub/docs/sim-cards-knowledge

NB-IoT / LTE-M Bands

Each Lobaro hardware only supports a subset of bands. 

Operators might change bands without prior notice. 

The NB-IoT Bands selected for Europe are B3 (1800 MHz), B8 (900 MHz) and B20 (800 MHz). B8 and B20 are supported by all Lobaro devices, B3 might be available on recent variants too.

Known issues

Remote Update for Modem Firmware not possible (relevant until today)

The Lobaro Hardware does not support remote Modem Firmware updates. This might change in future but brings additional hardware requirements like external memory.

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.

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