R410M: Connection time vs signal strength issues

For my internship I’m working with the SARA R410M module, whilst testing I’ve encoutered some contradicting data.
I’m using a Vodafone SIM card connected to the NB-IOT network. (here are my settings: https://imgur.com/0gIkHXK)

I’ve loaded the Sodaq-saraR4-maker software using Arduino.

I’m working on a project with in which battery life is very important. So I wanted to check how long it took for the module to connect. I noticed some strange patterns in which it would sometimes connect faster indoors compared to outdoors. After that I started checking signal strength using the AT command: AT+CSQ. The results of which can be found below.

One would expect that the time to connect would decrease as signal strength grows. Yet it appears to be random. I’m pretty sure these measurements are correct. I’ve done multiple tests on these locations and the times to connect were within seconds of eachother. So I suspect there to be another factor that affects the time to connect, yet I have no clue what.

Are there any of you that have encoutered a similar Issue?

Hi

I did not do investigations on how long it takes to connect in different situations but I have a general problem that it always takes very long time to connect, like 30 min or so.
When I at the end get response to AT+CSQ I get a signal strength of 31.
Maybe you have a suggestion what I could improve. I use the AT pass-through sketch and just pass these commands:

// Set NB-IoT mode
AT+URAT=8
OK
AT+CSQ
+CSQ: 99,99
//after approx 30min
AT+CSQ
+CSQ: 31,99

FYI: I am using Telia in Norway - but should not make a difference I think

Hi @Uta
I have tried the serial passthrough, but I haven’t been able to get it to work so far.
I have worked with an Arduino sketch (link below), which I have been able to get working. Kinda.
You could try this code. This code sends some data that can be seen using Allthingstalk. Might be worth a shot.

https://github.com/janvl1234/SODAQ_EVENT_ATT_MAKER

Thanks for your suggestion. You forgot the link ?

@Uta
The link is there now, oops. You do need to aqcuire a allthingstalk token though.

Have you set the band mask? It might speed things up.

If you are comfortable in Python we have an open source library for ublox modules. As of now we put a passthrough program on the arduino and just send from our laptops or some RPi

Thanks @Krolken!
I’ll check my code for the band mask, good idea!
I haven’t had the courage yet to dive into the world of Python, this might be the right moment to force myself to do so. Thanks for sharing your work!