Re: CDMA versus GSM

On Nov 17, 9:41 am, Ron Natalie <r...@xxxxxxxxxxx> wrote:
Darkwing wrote:

Just for the record I have Verizon which is CDMA, I went over to Europe last
month and my f%^&^& phone wouldn't work since all their networks are GSM. So
if you have GSM I think you got the better deal. Some US companies like AT&T
are GSM as a few guys had iphones that worked just fine. I ended up getting
an Orange prepay phone for the trip. In the future I am going to get a US
prepay phone before I travel overseas, I can't drop Verizon since I don't
have to pay for it!

If international compatibility is important to you, make sure you get
a quad band phone (and possibly one with UMTS...what ATT markets as
their 3G service). My quad band phone has worked everywhere with GSM
coverage and I believe now with the UMTS in it it will work in Japan.

My triband GSM unit failed to work in Australia as the missing band
was the one they used. There's a website out there by the way that
will tell you what bands and what carriers operate in each country.

This is a very complicated question. It is also one I've spent most
of my professional career trying to answer.

As a practical matter, both GSM and CDMA work and work pretty well in
most situations. If operation in multicontinents is important to YOU,
then look into the multiband units as Ron says above. Most people
don't really care about that and shouldn't incur the additional size,
weight, power, cost penaties associated with additional features that
never get used.

Right now, I happen to have two phones. One is on my personal account
- a Samsung SCH-u740 - and I love it. It is a new CDMA only, dual
band (800 and 1900 MHz), very small and light, full QWERTY keyboard,
EV-DO high speed data, etc. The other one is a Samsung i830
smartphone which I have on my company account. This one is both dual
band CDMA for the USA and 900 MHz GSM for Europe. It uses microsoft
mobile windows operating system and can directly access the web, etc.
I don't usually carry it with me because it's a good bit larger and
heavier than the 740 and I rarely need its additional features. I
spent a month in Europe this summer and got some good use out of it
there. Both of these phones have the ability to sync with my
desktop's Outlook calendar, contact and mail while mobile. I use this
a lot. I've also used the Pilot MyCast on the 740 for weather
briefings and to file flight plans while driving to the airport.
(mandatory aviation content for this posting)

As far as the question of which one is better, GSM or CDMA, it is my
professional opinion (which people pay me a lot for, but you're
getting for free) that CDMA is a significantly superior technology.
You could also consider that the Europeans have decided to use their
own version of CDMA which they call W-CDMA as their 3rd generation
upgrade. My employer makes chips for both of these, including some
which do both CDMA technologies (and even GSM).

In the USA, cellular uses both the 850 MHz band and the 1900 MHz
band. CDMA in the USA uses both of these, depending on your location,
carrier and roaming options. The higher band has a significantly
shorter wavelength which tends to allow it to penetrate through
windows better. However, path loss is a function of frequency
squared, so this amounts to a 7 dB greater path loss for 1900 MHz.
The mobile antennas can't make up for it because they must be smaller
in order to have omni-directional coverage. Base station antennas can
be made to have somewhat higher gain, but this only partially makes up
for the above loss. Hence, the range of coverage for a given site
would tend to be less for 1900 MHz. The 1900 MHz service providers
can make up for this by having a higher density of base stations in
their coverage area. Some do, some don't. Your coverage may vary.

K l e i n
.

Relevant Pages

  • Re: What is the best phone for reception in rural areas?
    ... It's extremely rare to find a place where there is GSM coverage but no CDMA coverage. ... For Telstra to sell its CDMA assets off, he told ZDNet Australia via e-mail, "would mean Telstra would be unable to service rural Australia effectively, as it would have to give up the 850MHz spectrum -- which is so good for rural coverage -- or even split that spectrum." ...
    (alt.cellular.cingular)
  • Re: The i-mateT PDA2k EVDO opinions ?
    ... (this will probably change when more people begin using the network) ... No built in Wi-Fi as on the GSM ... CDMA penetration is not as good as GSM (Building Walls / Underground ... Car Parks etc) although CDMA coverage is better than GSM. ...
    (microsoft.public.pocketpc.phone_edition)
  • Re: A Glaring Lack of the Obvious
    ... networks for CDMA and GSM. ... rather than *any coverage at all*. ... Also, at least until recently, many phones still supported analog (AMPS) ...
    (rec.arts.sf.written)
  • Re: Cheap phones suitable for poor coverage areas?
    ... GSM). ... coverage with fewer cells, even though every one of them would rather ... have been selling GSM, and not CDMA, handsets (CDMA handsets are ... a match for the coverage footprint of a CDMA cell, ...
    (uk.telecom.mobile)
  • "www.roxyhp.com" Spesifikasi Handphone Hi-Tech
    ... Battery: Li-Ion 1100 mAh,standby time 200 h,talk time 3.30 hours ... Band: GSM 900 / 1800 ... Display: Touch Panel,TFT QVGA,320 x 240 pixels, 262.000 color ...
    (soc.culture.indonesia)