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This is a sub-selection from Question is though

clone

join:2000-12-11
Portage, IN
Reviews:
·T-Mobile US
reply to ArizonaSteve

Re: Question is though

I have seen people post about this before, and I think many readers are very confused. For simplicity's sake, let's use the proper terminology for the network technology here. There are currently 3 GSM network types available:

1. Original 2G GSM which includes GPRS and EDGE data standards. T-Mobile runs a GSM/GPRS/EDGE network in the PCS 1900MHz band. It uses a TDMA-based air interface.

2. 3G GSM. This is actually called UMTS (Universal Mobile Telecommunications System). This includes HSDPA/HSUPA (which combine to form "HSPA"), and HSPA+21, HSPA+42, and HSPA+84 data standards. T-Mobile currently runs a UMTS/HSPA network, which in many areas is upgraded to HSPA+ (21, 42, etc.) in the AWS 1700/2100MHz band. It uses a Wideband (5MHz channel) CDMA air interface called, wait for it, WCDMA.

AT&T runs one of these networks, too, and they also call it 4G (even though it's a 3G network at heart). It runs in the 850MHz Cellular and 1900MHz PCS bands. This is important, as every iPhone ever made is designed with 850/1900 in mind for AT&T users. This is why T-Mo is starting to offer *limited* UMTS service on the 1900MHz band, so they will be compatible with the other large UMTS carrier in the United States.

3. 4G LTE. This is the "Long Term Evolution" network. Completely IP-based. Includes the LTE Advanced standard. T-Mobile does not have one of these, yet. Verizon, AT&T, and Sprint currently have live LTE networks in the United States.

T-Mobile's 3G and 4G service are exactly the same service/network/cell sites, etc. The "4G" service is just a term their marketing department is using to describe their HSPA+network. HSPA+ is just software revision of their original 3G standard. So if your phone is compatible with T-Mobile 4G, it is also compatible with T-Mobile 3G.

So, why would you even want 3G on 1900MHz (PCS), when you are already getting it on 1700/2100MHz (AWS)?

Iin T-Mobile world, if you have any UMTS/WCDMA based service (short of the very few cities currently offering UMTS on PCS), from standard UMTS data/voice all the way up to HSPA+42, you are using the same network and towers as every other T-Mobile 3G/4G user.

All that being said, I don't believe T-Mobile is decomissioning any UMTS-based services in the AWS band as of yet. Considering 100% of their installed userbase (that is not still using a GSM-only handset) is currently using UMTS in the AWS band.


Bahamut X
Premium
join:2000-12-09
Fort Worth, TX
said by clone:

So, why would you even want 3G on 1900MHz (PCS), when you are already getting it on 1700/2100MHz (AWS)?

A) International telephones/the iPhone.

Take any Eurospec phone (International Galaxy devices pre-GS3, HTC devices) or an iPhone, and since the T-Mobile AWS frequencies are typically not supported on these phones. Opening up the 1900 MHz freq. to greater than EDGE speeds means these phones can/will work to their full capacity.

B) The LTE rollover.

Almost all of the newer T-Mobile phones released actually do support both AWS and PCS 3G/4G frequencies. It is easier for customer usage to upgrade the GSM network finally instead of building into the AWS frequencies. This permits new phones to continue using their fully capable high speed radios whilst giving the ability for T-Mobile to free up the AWS spectrum for LTE deployment. Just have to look at those customers still using older GSM telephones and potentially upgrading them to something... newer.

3) Penetration:

Correct me if I'm wrong, but wouldn't 1900 MHz spectrum give "marginally" better building penetration than a 2100 MHz spectrum buildout?
--
I work at T-Mobile. I play games and enjoy time off of work. I've been a member here longer than I've worked there. I have my own opinions, they do not hold anything to T-Mobile USA, etc etc etc...

clone

join:2000-12-11
Portage, IN
Reviews:
·T-Mobile US
I was just referring to the OP, who was concerned that his T-Mobile branded AWS compatible phone won't work on PCS 3G/4G. There is no reason to be concerned about 1900MHz UMTS on a phone that will probably be an artifact by the time AWS is deprecated.

I realize there are huge benefits to using compatible frequencies both for handset availability/cost and roaming, etc, and that the AWS spectrum will eventually be re-farmed for LTE. T-Mo's spectrum plan is a good one, I just wonder why some people are so concerned about it.

As for penetration, the base station-to-handset channels in the current AWS spectrum should theoretically provide better in-building coverage than PCS, while the handset-to-base station channels are theoretically worse. In everyday use, I don't see much difference between AWS and PCS.

ArizonaSteve

join:2004-01-31
Apache Junction, AZ
Reviews:
·voip.ms
·CenturyLink
reply to clone
Clone said: "T-Mobile's 3G and 4G service are exactly the same service/network/cell sites, etc. The "4G" service is just a term their marketing department is using to describe their HSPA+network. HSPA+ is just software revision of their original 3G standard. So if your phone is compatible with T-Mobile 4G, it is also compatible with T-Mobile 3G."
That seems to be a myth a lot of people are spreading but is Absolutely NOT TRUE! Use the OpenSignalMaps site or the Android app and you can see the different locations of 3G and 4G towers.
In the Phoenix area 3G and 4G are on different towers even though both are on 1700Mhz and 4G is only available near T-Mobile stores while 3G is not! 3G uses HSPA+ while 4G uses WCDMA. There are 6-7 2G and 3G towers around me but only 1 4G tower about 2 miles away so it's too weak to pickup. Note that OpenSignalMaps says T-Mobile 4G is 3.5G.
My 4G Samsung Exhibit II gets only 4G with WCDMA and CANNOT get 3G using HSPA+ even though they are both on 1700Mhz. Yes, I know they are similar protocols but certainly not interchangeable.

clone

join:2000-12-11
Portage, IN
Reviews:
·T-Mobile US
Please, do some research before you make yourself sound any more uninformed. Not to get into a pissing match, but trust me. I know what I'm talking about.

UMTS, Universal Mobile Telecommunications System (link)

Specifically, see the releases at the bottom. HSPA+ is the name of a revision of the data protocol. WCDMA is the air interface that protocol (and all of the UMTS family protocols) use.

Pro Tip: OpenSignalMaps data is garbage. I can force my phone to "GSM ONLY" mode (or have a European Android phone that has no USA 3G bands on it), then be the only person who has reported signal from a given cell site. Now, according to OpenSignalMaps, that is a "2G" tower, even if in reality the site is also an HSPA+84 site. (Just an example of how the data can be skewed.)

If your phone shows that you are getting "4G", that is 3G HSPA+. Marketing departments have utterly confused you (and most consumers).


Bahamut X
Premium
join:2000-12-09
Fort Worth, TX
reply to ArizonaSteve
said by ArizonaSteve:

Use the OpenSignalMaps site or the Android app and you can see the different locations of 3G and 4G towers.

If I use that site sitting at home... or work... or any other place I happen to travel west of downtown Fort Worth, then by THEIR site, I should have 0 signal. Nothing at all, be it 2G or 3G based services (UMTS, HSPA of any flavor, et al).

I'll sit here and believe my phone and my tablet, which is telling me that it has access to HSPA based speeds, over a 3rd party site that tells me I should have nothing at all...

Or better yet, the T-Mobile engineering map (which the link is liberally posted around here), which also shows I should be able to max out whichever device I have sitting around me.

@clone: This gentleman (ArizonaSteve) has had many times been shown how his information can be... flawed, but yet, continues to state that somehow his UMTS based device can only get "4G" service, can fall back to EDGE, but cannot somehow access "3G" towers, despite the fact that both the marketing "4G" and the factual "3G" are the same thing. One example can be found here where, once facts started coming out, esp comparing frequency bands on various phones, he kinda... disappeared.

Facts are facts. Marketing says the new stuff is "4G" (although true 4G comes next year... wonder how they'll spin it, even though it's just 3G with a supercharger attached), but it all uses the same base UMTS setup on the AWS spectrum (and soon PCS spectrum). There is no differing "3G" and "4G" towers, though it could be possible a tower has not been upgraded from 7.2 mb/s standard to the newer HSPA+ standard, but even then, the phone would still show potentially only a "4G" signal (unless rooted, then Cyanogen might show either "H" or "3G", I've seen both on my rooted Galaxy S2).
--
I work at T-Mobile. I play games and enjoy time off of work. I've been a member here longer than I've worked there. I have my own opinions, they do not hold anything to T-Mobile USA, etc etc etc...