nRF9160 max transmit power

RE: nRF9160 max transmit power

Frikkie Badenhorst — Thu, 08 Jul 2021 14:39:36 GMT

Thanks so much for you response, Heidi. It is extremely helpful.

I hope you have a lovely summer time in Norway.

RE: nRF9160 max transmit power

Heidi — Thu, 08 Jul 2021 13:18:01 GMT

Hi!

ue-PowerClass-N, ue-PowerClass-5 indicates whether the UE supports UE power class 1, 2, 4 or 5 in the E-UTRA band, see TS 36.101 and TS 36.307.

If neither ue-PowerClass-N nor ue-PowerClass-5 is included, the UE supports the default UE power class in the E-UTRA band, see TS 36.101 [42].

So the lack of powerclass in the capabilites means that the UE only supports the default power class 3.

If powerClass were to exist in capabilities, it would be in

rf-Parameters-v1320 {
supportedBandListEUTRA-v1320 {

Best regards,

Heidi

RE: nRF9160 max transmit power

Frikkie Badenhorst — Tue, 06 Jul 2021 12:24:56 GMT

Hi Heidi,

Thanks for the response it does provide some clarity on this. Here is a text file containing the uplink UE capabilities information that we are seeing during the attach procedure. devzone.nordicsemi.com/.../2816.nordic_5F00_capabilities.txt

I unfortunately do not see any reference to the power class of the device? Could you please point me to the location in the uplink message which I have attached where this is specified?

RE: nRF9160 max transmit power

Heidi — Tue, 06 Jul 2021 11:25:51 GMT

Hi!

Looks like you've gotten some answers already.

1) The max allowed power of the device is 23 dBm. It's decided by the base station and not configurable by the UE.

2) AT%CONEVAL will give you the actual transmit power of the UE.

The nRF9160 is only certified as a PC3 device, so a max power of 23 dB.

The UE has to send capability information to the network cell as a part of the attach procedure, and the power class is a part of this information.

Best regards,

Heidi

RE: nRF9160 max transmit power

Frikkie Badenhorst — Tue, 06 Jul 2021 09:39:43 GMT

Hi Bjoern, thanks. Would you then please assist in your understanding/knowledge of devices with different power classes.

Lets say for example we have a power class 3 device (max transmit power of 23dBM) and a power class 6 device (max 14dBm). How does the base station then know which device has a max power of 14 and 23 dBM respectively? Is this included in an uplink message somewhere? Or does the base station not know this, and if the base station for example tells the 14dBm device to be "set" to 23dBM, it will just force itself to 14dBm since that is its max transmit power?

We have seen some modules from different manufacturers that supports AT commands in which you can set the max transmit power of the device and was thus wondering if Nordic also allows this (thus increasing the power class of the device)?

I hope the questions are clear - if not please let me know as it is important for us to understand this.

RE: nRF9160 max transmit power

BjoernS — Mon, 05 Jul 2021 15:44:56 GMT

As far as I know that is not possible since the base station is making the decision what TX power the UE has to use.

RE: nRF9160 max transmit power

Frikkie Badenhorst — Mon, 05 Jul 2021 09:47:29 GMT

Hi,

Looks like v1.3.0 came out recently and we were not aware of it. We have upgraded the firmware and are successfully able to test the AT%CONEVAL command to see the actual transmit power.

Thus, question 1) is the only question outstanding:

[quote userid="105759" url="~/f/nordic-q-a/76998/nrf9160-max-transmit-power/318146#318146"]1) What AT commands can we use to see/edit the max allowed power of the device?[/quote]

For example is it possible to set the maximum allowed tx power from 23 to 14dBm if we for instance know that the device is close to a base station?

RE: nRF9160 max transmit power

BjoernS — Mon, 05 Jul 2021 08:45:47 GMT

Hi,

the AT%CONEVAL AT command is only available if you are using the modem firmware version 1.3.0 and above. Have you checked if you are using this firmware version on your nRF9160?

RE: nRF9160 max transmit power

Frikkie Badenhorst — Fri, 02 Jul 2021 08:05:44 GMT

Hi,

Can someone please assist with this issue as soon as possible as it is quite urgent?

I have come across the AT%CONEVAL AT command, which I believe can be used to see the actual transmit power of the UE. Unfortunately we are not able to use this command, as we are getting the "ERROR" response when attempting to use this every time.

RE: nRF9160 max transmit power

Frikkie Badenhorst — Thu, 01 Jul 2021 10:31:40 GMT

We have managed to fix this issue from the base station side. However I do still have the following questions:

1) What AT commands can we use to see/edit the max allowed power of the device?

2) What AT commands can we use to see the actual transmit power of the device?