nRF9160 with NB-IoT in Switzerland

RE: nRF9160 with NB-IoT in Switzerland

Hakon — Thu, 29 Jul 2021 14:54:58 GMT

[quote user="Matthias K"]I know this might not be a Nordic issue, but I'm not sure how I would safely know that my device is in a region with only NB-IoT available (and no M1).[/quote]

From reading the 3GPP spec, my interpretation is that E-UTRAN in nb-s1 mode is equivalent with NB-IoT.

"NB-IoT is a non-backward compatible variant of E-UTRAN supporting a
reduced set of functionality."

So if it says "9 – E-UTRAN NB-S1", it should mean that NB-IoT is available exclusively. And because it is non-backward compatible, 7 – E-UTRAN should be exclusively for Cat M1.

I have no way of confirming this at the moment, since the modem team is unavailable for the moment.

RE: nRF9160 with NB-IoT in Switzerland

Chraebs — Thu, 22 Jul 2021 14:51:12 GMT

Yes I know I can check the general 3GPP spec (especially 3GPP TS 27.007 section 10.1.22). But appologize my ignorance: From a logical point of view I'd expect at least 3 different variants:

1. Only LTE Cat M1 available
2. Only LTE Cat NB1 available
3. Both variants available
The 4th case "No variant available" is not necessary, as we wouldn't register to a cell then.

But according to Nordic and 3GPP spec, only two options are applicable:

<AcT>

7 – E-UTRAN

9 – E-UTRAN NB-S1

are listed in https://infocenter.nordicsemi.com/topic/ref_at_commands/REF/at_commands/nw_service/cereg_read.html?cp=2_1_7_7_1. I know this might not be a Nordic issue, but I'm not sure how I would safely know that my device is in a region with only NB-IoT available (and no M1). ... ...

Thus I don't see a meaningful way to check which variants are available..

RE: nRF9160 with NB-IoT in Switzerland

Hakon — Thu, 22 Jul 2021 14:27:50 GMT

You can check the 3GPP spec, I believe you can find a detailed explanation about the AT command response there. There is also this document, but I'm not sure how helpful it is. You can read more about the EUTRAN definition here.

RE: nRF9160 with NB-IoT in Switzerland

Chraebs — Thu, 22 Jul 2021 14:01:24 GMT

Can you point me to some explanation of the <AcT> field in the AT+CEREG response (EUTRAN vs EUTRAN NB-S1)?

RE: nRF9160 with NB-IoT in Switzerland

Chraebs — Thu, 22 Jul 2021 13:59:31 GMT

Ok thanks Hakon this corresponds to what I figured out in the meantime. It seems that for the iBasis SIM roaming is not allowed for NB-IoT in Switzerland yet (roaming in Switzerland with iBasis SIM is only available for LTE M1).

I checked with the local network providers. Even their own regular SIM cards do not support NB-IoT but only some dedicated IoT SIM cards. For those, they claim having roaming arrangements for most parts of Europe and world wide (but less than for LTE M1).

RE: nRF9160 with NB-IoT in Switzerland

Hakon — Thu, 22 Jul 2021 13:52:55 GMT

Hello,

there is no coverage for NB-IoT for iBasis in Switzerland yet. You will need to contact iBasis or the local carrier if you need more details.