nRF9151 Power consumption over NTN

[Jostin]

Hi everyone,

I am currently working with Circuit Dojo nRF9151 using nRF Connect SDK v3.0.1.

When measuring power consumption over MQTT and UDP, i noticed ~25mA every ~1.4s when using NTN, what is not the case on LTE-M. Someone knows how to reduce or eliminate it ?

Setup :

Firmware : mfw_nrf9151-ntn_1.0.0-1.alpha

PSM/eDRX : enabled

Protocols : MQTT & UDP

Crucially, it disappears immediately once the socket is closed

Questions:

1. Is this 1.4s cycle a mandatory requirement for NTN synchronization to handle Doppler/latency?

2. Is there a way to trigger a faster RRC Release without manually closing the socket every time (already used RAI)?

3. Has anyone managed to get a "clean" RRC-Idle state (no spikes) while keeping a TCP/UDP socket dormant in NTN?

Jostin

[Øyvind]

Hello, are you able to provide more information on the steps that you are using? What application are you running?

What SIM are you running in order to connect with an NTN constellation, GEO or LEO? 

I am currently working with Circuit Dojo nRF9151 using nRF Connect SDK v3.0.1.

When working with NTN we recommend using the nRF9151 SMA DK to ensure the best antenna for the application. I would recommend looking at the Evalute NTN on the nRF9151 SMA DK product page.

Kind regards,
Øyvind

[Achim Kraus]

In my experience in the last 6 months the nRF9151 feather works pretty well with NTN/GEO. In difference to the DK, it's possible to run the device from battery. But in order to make measurements and tickets, I would also recommend the use a DK.  

> Has anyone managed to get a "clean" RRC-Idle state (no spikes) while keeping a TCP/UDP socket dormant in NTN?

I haven't checked that in the last months, but with NTN/GEO everything takes longer.

Anyway, 

Øyvind said:

What SIM are you running in order to connect with an NTN constellation, GEO or LEO? 

That's pretty crucial to know, what you're using. Otherwise it's not possible to compare the outcome.

Once the info is available, I will try to retest my setup (Deutsche Telekom SIM, GEO/Skylo, nRF9151-feather, NCS 3.2.4, CoAP/DTLS 1,2 CID/UDP, PSM, on eDRX).