Data plan question: does the nrf91 need CAT-M1 support to work?

[jrowe]

Hi!

I am in the process of  trying to figure out how much it is actually going to cost for our devices to support LTE-M, and I have realized that I don't actually know what the data plan requirements for the nrf91 chipset are. I apologize for asking what sounds like a question that a quick google search should be able to answer, but I have tried that and I am still pretty confused. There are a lot of acronyms being thrown around, and I am hitting the learning curve pretty hard.

From what I can tell, the nrf91 is designed to work with carriers that support CAT-M1. I haven't seen any documentation from Nordic on this, but I have read in other places that LTE-M is compatible with existing LTE networks (4g, etc), but these networks will not allow the device to go into power saving mode (PSM). Is this understanding correct? Does the nrf91 NEED CAT-M1 coverage? is CAT-M1 coverage required for the device to go into power saving mode? If not, what is the value of a data provider that supports CAT-M1?

thanks for tolerating such a basic question

[Martin]

About the networks:
The nrf91 needs a LTE-M1 or NB-IOT network.
One way to implement LTE-M is  on top of an existing 4G infrastruture with just some software updates.

About SIMs/data plans:
At the moment some SIM cards that work for 4G also work on LTE-M and to a lesser extent in NB-IOT.
But normally you should get specific SIM card and data plan for LTE-M and NB-IOT.

About network capabilities:
A lot of networks are not yet implementing all possible power save modes (PSM, eDRX, etc) or non at all.
This means that the modem still works but might be almost impossible to use the GPS at the same time as it shares the same RF path and the RF path never gets released from the mobile network.

So why bother with the nrf91:
- incredible integrated package with CPU, RAM, Flash, Modem, GPS, SPI, UART, I2C, etc
- Less expensive
- Software SDK with easy socket interface (basically no AT commands needed)
- Way less power than traditional 2G, 3G, 4G external modem

But at the moment almost impossible to get  a world wide coverage because the network operators are not ready/willing/roaming ...

[jrowe]

Thanks,

This was extremely helpful.