network systems questions..... what are differences?

[Thanh]

Hello :)
I have a question regarding network systems.
I know GSM as i use it... but:
What is the difference between CDMA and CDMA2000-1x?
What is CDMA 800 (analog/digital)?
What is TDMA?
What is the difference between AMPS and "tuned AMPS"?
The reason for my question is, i want to know which Nokia i could use on Bangkok's HUTCH network (CDMA2000-1x) and what networks do phones such as the 8260 (TDMA/tuned AMPS) or 8285 (CDMA 800/AMPS) work on, and which system the Nokia 282 uses (an analog flip phone!)...... I think the thread is misplaced in CDMA section as i have no problem with any such phone, just want some info about the systems themself.
Thank you very much in advance....
your Thanh

[Yotamz]

you have many questions here, but i'll try to give you answers for them..

1. the cdma 2000, and cdma 2000-1x are advanced versions of the original cdma (Code Division Multiple Access) technology . the difference is primarily the speed. there is also one more advanced cdma version (i think it's called cdma2000-ev-do or somthing like that).
2. as much as i know cdma 800 is digital (i have a digital cdma 800 phone myself)
3. tdma (Time Division Multiple Access) is another type of network, slower and less advanced than cdma and gsm, but also in use by many networks. (it has nothing to do with cdma).
4. i'm sot sure about amps, but i know that it's an analogue system that works on 800 Mhz.

on a digital cdma network like the cdma2000-1x, you can use any digital cdma phone, also those that are not designed to support the new cdma2000 technology.

hope this information helps you :)

[Thanh]

Hey thanks a million!
That was a nice piece of information! I was searching the net but i could not get answers as clear as yours!
In fact, i was looking for a way to possibly become a user of the "Hutch" network here without having to buy one of the two Sanyo-phones this provider offers. It is a CDMA-2000-1x network and is based on an upgraded older CDMA network, which never jad more than 5000-6000 users, as it works only in greater Bangkok and is sh!t expensive.
Now, does it mean i could just try to get hold of an american Nokia model with CDMA and then go to Hutch and apply for a number? They have no SIM cards, rite?
And, final question, is it possible to send SMS from a CDMA-Network into a GSM network and vice versa, i mean, do they use the same standard?
Thank you again.......
Kind regards...
your Thanh

[Yotamz]

some cdma phones (newer ones) do have sim cards. (the cdma simcard are not called sim, they have another name, don't remember what it is). anyway, if you have a cdma phone without a sim, you can't just take your phone to every country you want like you would take a gsm phone, you have to give the phone to the new network (Hutch in your case) so they will program it to use their network. you must program the phone as variuos networks use different settings, and also you must get a number.

in theory you can just buy a cdma phone somewhere and use it, but i know that some networks (like Pelephone in Israel) don't accept any phone you give them, and they may decide not to connect your phone to their service, and you'll be left with a phone that you can't do anything with.
i suggest that you call Hutch, and ask them if it's possible. (they may ask you the phone model). also, make sure thet the phone you buy uses the correct band (800 Mhz, etc.)

that's pretty much it..
good luck :)

p.s.
if you are going to buy a phone anyway, wouldn't it be easier to buy a gsm phone that you can use with your sim?

[Yotamz]

about sms, it's not that simple to send sms between a cdma network to a gsm network bacuse they don't use the same standard, but it's up to the provider. every sms you send goes through the operator's sms gateway, and the operator delivers it to the destination (if the destination is in another network it will forward it to that network). so, if the operator have the equipment needed you will be able to send sms from your cdma phone to a gsm network's phone.

here in Israel we have 4 networks, with 4 different network types (GSM, CDMA, TDMA and IDEN). at the beginning you couldn't send sms from one provider to another. later they made it possible to send sms between some of the networks but not all, and now it's possible to send sms to every network you want :) (it's very expensive, but still possible).

[Thanh]

Thanks a lot, my friend!
In my case it is not just "getting a new phone" as i had plenty of them and i am very happy with GSM... it is just that i always want to test new, or other, technolkogies... if possible, without having to spend much money as i am actually dirt poor.
The CDMA system is interesting for me only because it sort of new here, even it has been used for a decade or so, but never had many customers, only recently Hutchinson took it over from CAT and renamed it to "Hutch" and upgraded to the new standard. But they offer only two phone models, both flip (i don't like flip phones) and also i don't need a camera or a 65k colour screen only to explore the CDMA technology. An old Nokia would do... besides i prefer Nokia anyway over those Sanyo's although thy look actually quite nice....just they are flip phones.
Now, i am yet shy to goi there and ask for details as they sure will tell me "it is impossible" which is kind of a thai standard... if they don't want to do something, they just say "it is impossible" or "we don't have it" even everyone can do it......
Hmm about this frequency thing, that's why i asked initially the difference between those CDMA systems "CDMA 800" and "CDMA 2000-1x" :) Do you have an idea which Nokia model could use any of those and is cheap to get (second hand of course)..? Thank you very much for your help......
Kind regards...
your Thanh

[Yotamz]

i've been searching the network for cdma, but there wasn't any site that mentioned the frequency thing, what makes me think that the all the cdma networks (cdma, cdma2000, cdma2000-1x) uses the same frequency, the difference is that usa networks work on the 1900 Mhz frequency.

anyway, there are many nokia phones you can use.
you can find some here:
http://www.nokia-asia.com/
or if you want to buy a phone in use go here:
www.nokiausa.com/phones/
most of the nokia cdma phones ends with 8x (like 8280 or 3586i).
look in each phone's specifications to find which frequency it supports.

if you want more information about cdma you can go to www.cdg.org - the cdma development group site.