I have a project which uses an LTE-M (also called LTE Cat-M1) cellular module which doesn't work well outside the city, while my phone works fine. Sending SMSs usually works with the cell module, but it doesn't receive them... the doesn't see incoming SMSs until IT sends one and makes that strong connection to the cell tower... then it realizes oh, there are incoming SMSs I need to receive.
There are a few things I imagine this would be due to:
1.Difference in protocols: LTE-M is broadcast different that LTE Cat 4 at the tower (de-prioritzed, lower power, something else because networks care less about M1 than Cat 4)
2.Difference in power: The cellular module doesn't power the antenna as much as my phone does - would the amount of power be the responsibility of the cellular module designer or the breakout board designer? This is the main question I have, because I could find the same module on a different breakout, or I could find a different module on the same breakout form factor.
3.Difference in design: The cellular module and antenna are cheap compared to the components in my phone