What prevents the usage of LTE on AT&T and T-Mobile?

[bntran0410]

So as most of you probably know the new droids can be used on pretty much any GSM network as of now with HSPA+. But after looking at the LTE frequencies supported on the new droids I dont see why it can't connect to LTE on AT&T or TMobile.

I don't plan on doing this anytime soon with my new Droid MAXX but I can see a possible scenario two years later when i'm off contract again.

So...why can't the new droids be used with AT&T or TMobile's LTE?

 

[kg4icg]

Because TMobile and AT&T do not have a LTE roaming agreement that is why.

 

[bntran0410]

Um...You misunderstand and maybe I could be clearer. If I take an AT&T or TMobile sim card (that fits) and plug it into the new droids then it will just work: http://www.droid-life.com/2013/08/22/droid-ultra-can-connect-to-atts-hspa-network-out-of-the-box/

At this point Verizon is out of the picture entirely and no roaming agreements are necessary. Verizon is also not legally allowed to carrier lock their phones due to some agreement a while ago. So does anyone know why the new droid phones cannot connect to AT&T or T-Mobile's LTE if we just plug in their respective SIM cards?

 

[kg4icg]

Thing is say you put a TMobile sim in your phone. TMobile doesn't use the 700 mhz band for LTE so it isn't going to look for it, and since there are no roaming agreements on LTE with AT&T it isn't going to try, like wise for the reverse. Only carrier that has LTE roaming agreements is Sprint in the Asia/Pac, South America on the 2500/2600 band which is LTE-TDD which is LTE Advanced.

 

[bntran0410]

You're going back to roaming agreement but I still don't see how it matters.


CASE 1: plug in AT&T Sim. AT&T uses 700mhz block B while the DROID uses block C. So I understand why that part won't work. What about the DROID's supported 1700/2100mhz band is also supported and in use with AT&T.

CASE 2: plug in TMo Sim. They use 1900 and 1700/2100mhz for LTE. 1900mhz won't work for droids but why not 1700/2100 aws?

Again, if you plug in a carrier's Sim card why would it need a roaming agreement to roam onto itself?

Posted via Android Central App

 

[kg4icg]

AT&T don't use AWS for anything currently. TMobile uses AWS 1700/2100 which is where TMobile has there LTE.

 

[cliberti]

And, although the DROID supports AWS it is not enabled yet and probably won't be until Verizon rolls it out.

 

[Brian Phipps]

What was the agreement that prevents them from carrier locking?

Posted via Android Central App

 

[goldkear]

What was the agreement that prevents them from carrier locking?

Posted via Android Central App

I think Google tried to outbid them for the frequency, or at least forced them to pay more by bidding on it, and at a certain threshold they were forced to have their LTE network open. Its sort of a moot point though since they have control of their CDMA network.

 

[Paynefanbro]

Just as 700Mhz is split into blocks, so is AWS (2100/1700). Verizon runs off of a different block of AWS than T-Mobile. As a result, Verizon has a specific set of parameters in place in terms of software that prevents it from switching over to T-Mobile's network. Same with Sprint devices. Sprint devices that aren't world phones (CDMA/LTE only) can run on GSM, but through a carrier limitation, they have the GSM radio turned off and only available for emergency calls.