Tx Power Read/Predict/Limit

[jtbrauer]

Hello,

When looking at the datasheet, we see that the modem power consumption can be really high in high power tx scenarios, 23dBm for example the modem consumes almost 300mA! We are a very power constrained application, so are pretty worried about this number. 

Is there any way to read, predict, or limit the transmit power to prevent this current consumption from happening? Ideally if we could limit the TX power, even at the expense of connecting, that would ensure we are able to stay under our current budget. Otherwise being able to predict based on RSSI or read it to disable the modem in those cases would be next best option.

Thanks,

Jordan

[Kazi Afroza Sultana]

Hello,

When sim tries to connect to network there should be highest peak current. I can not see any way to limit the transmit power to prevent the high current consumption happening. However I have asked my team about this. I will get back to you soon. 

Thanks

Best Regards,

Kazi Afroza Sultana

[Kazi Afroza Sultana]

Hello,

As I said before, the highest peak current is during data transfer, when the TX has a high duty cycle. The TX power can not be controlled by the application. It is determined by the Base station. 

We have an API which can be used to know the current connection quality of the modem, and the application can make decisions based on this. The LTE link can be controlled through library configurations and API calls to enable a range of features such as specifying the Access Point Name (APN), switching between LTE network modes (NB-IoT or LTE-M), enabling GNSS support and power saving features such as Power Saving Mode (PSM) and enhanced Discontinuous Reception (eDRX).

This library provides functionality that enables the application to receive notifications regarding LTE link parameters such as Radio Resource Control (RRC) mode, cell information and the provided PSM and eDRX timer values.  

Here is the link of API https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/libraries/modem/lte_lc.html?highlight=connection%20evaluation#connection-pre-evaluation 

Thanks.

Best Regards,

Kazi Afroza Sultana