Originally posted by HadE55NowM5:
<snip> Apparently, not only the TDMA AT&T platform operates at both of these frequencies -- Verizon (which was AirTouch + Bell Atlantic + GTE + PrimeCo) also plans to operate on 800mhz and 1900mhz (typically on the CDMA side). Apparently 1900mhz is in vogue due to the fact that this frequency allows for Mobile Messaging and Browser capabilities. <snip>
Here I can contribute my non-M5 expertise. This is about phones and frequency bands, not about M5's or even the phone in the M5- so read on only if interested.
Back in the days of analog cellular phones, there were two carriers per market (in the U.S.) allowed by the FCC. Both shared an 800Mhz band. This system was (and is) called AMPS. Newer digital technologies promised to make more efficient use of the same frequency spectrum, allowing more calls in the same cell (and larger profits for carriers.)
There are multiple digital protocols in use today - they are TDMA (AT&T Wireless, primarily), CDMA (Sprint, GTE/BellAtlantic/Verizon, Airtouch, U.S. West, others), GSM - Pacific Bell, Southwestern Bell, OmniPoint) and iDEN (Nextel, SouthernLinc.)
GSM is not very popular in the U.S. but is the ONLY standard in most of Europe. Asia has a few of their own, but uses both CDMA and GSM predominantly. Latin America is mostly TDMA.
Now then - these digital standards are nothing more than software protocols - they can run at any legal frequency. In Europe, the legal frequencies are 900Mhz and 1800Mhz. In the U.S. they are 800Mhz and 1900Mhz.
There are a few "world phones" on the market now that use the GSM protcol, and operate on both U.S. and European frequencies - either 3 out of 4 or all 4 bands. These are referred to as "tri-band" phones.
Several years ago, the 1900 Mhz band was made available by the FCC and auctioned to carriers as the "PCS" band. At the same time the FCC decided to allow more competition - so more than two carriers could serve a market - but the new carriers had to use the PCS frequencies.
The incumbent carriers (in my area, GTE and AT&T) could ALSO compete in the auctions for the PCS frequencies, and succeeded in many cases. So they have systems that operate on both frequencies. In most cases, "dual band" implies digital operation at a PCS frequency, with a fall back to analog operation at 800Mhz. New "pcs" carrers like Sprint that didn't have their own 800Mhz stuff can still offer dual-band phones but when you use the analog side, you're actually using a different carrier's network and paying high roaming charges.
However, it isn't that simple. Some carriers (like AT&T and GTE) have digital systems operating both at 800 and 1900Mhz, AND analog systems at 800Mhz. A phone that works on all of these would technically be referred to as a dual-band, tri-mode phone.
As for the browser stuff enabling email and internet access - my company, Phone.com, invented the technology in use by every major carrier in the U.S. (and most around the world). The Motorola phones with browser caabilities have Phone.com software in them. Thanks to Phone.com I am the proud owner of an M5!!!
It is not the case, however, that this capability requires 1900Mhz. Once again, this is all software and protocols and is actually frequency independent. GTE, for example, converted a lot of their AMPS systems to CDMA at 800Mhz. That system supports wireless data. Sprint's network uses exactly the same CDMA protocol to support voice and data at 1900Mhz.
Wireless data capability is a new layer on these networks, and the implementations and subtleties are many. If you get a Motorola phone on the TDMA network, it will NOT have browser capability. AT&T doesn't support wireless data over TDMA. It will only have 1-way short message service, AKA "SMS". This is because AT&T's current data solution uses their old, but good "CDPD" packet data network for data - this runs on top of the AMPS system. AT&T sells today only two phones - the Mitsubishi MA250 and an Ericsson model - that are dual-band, "quad mode" phones- 1: 1900 mhz TDMA voice; 2: 800Mhz TDMA voice; 3: 800Mhz AMPS voice; 4: 800Mhz CDPD data.
The same Motorola phone for CDMA markets (7000 and 8000 models) on the other hand, has the browser because those networks support wireless data natively.
Bottom line is if you want the wireless internet on your M5 phone, get a CDMA-based service. I haven't talked to the dealer, so I don't even know if they give you the choice.
Confused yet?
/Greg