WCDMA/UTMS versus GSM

[Mike]

Gotta remember Japan uses WCDMA/UTMS and US uses GSM so Japanese phone does not have SIM card unless you buy the one made to go roaming internationally. Like the V801SH from Vodafone and other models from AU. Vodafone uses USIM card and is not compatable with American SIM cards (unfortunately...)
I have both Sharp V801SH and GX32 since I go back to Japan often, I don't want to pay high price for rental phone when I go to Japan.

[jesus_thats_gre]

NTT DoCoMo do not use UMTS but use an alternative standard that is also based on WCDMA but is not cross compatible with UMTS as far as I know...

The Vodafone network in Japan uses both GSM and UMTS as far as I know..

Most American networks use CDMA based networks that are not compatible with GSM or UMTS based phones.. ATT in the states use GSM but were recently taken over by Cingular who operate on a CDMA based standard, so this may change in the future.

Most GSM networks are evolving to UMTS..

[fadedevolution]

GSM is growing fast in the United States. T-mobile, ATT, Fido, Rogers, and Cingular all run off of GSM. T-mobile alone last quarter had over a million new customers, while Verizon grew by a small fraction of that number, and lost thousands of customers to GSM technology.

Cingular, who bought out ATT, uses GSM, not CDMA dude.

[Mike]

Right, US still uses other system like AT&T, the TDMA (fading out) and Verizon uses CDMA, but majority is GSM

Originally posted by fadedevolution
GSM is growing fast in the United States. T-mobile, ATT, Fido, Rogers, and Cingular all run off of GSM. T-mobile alone last quarter had over a million new customers, while Verizon grew by a small fraction of that number, and lost thousands of customers to GSM technology.

Cingular, who bought out ATT, uses GSM, not CDMA dude.

[Mike]

Wide Band CDMA used in Japan is way better than the narrow banded GSM system used in the US. Yes, there are GSM system used in Japan, but their encryption scheme is different from US GSM system. There are so many different types of transmission protocol, I hope in the future there will be a international standard world wide.

Originally posted by jesus_thats_gre
NTT DoCoMo do not use UMTS but use an alternative standard that is also based on WCDMA but is not cross compatible with UMTS as far as I know...

The Vodafone network in Japan uses both GSM and UMTS as far as I know..

Most American networks use CDMA based networks that are not compatible with GSM or UMTS based phones.. ATT in the states use GSM but were recently taken over by Cingular who operate on a CDMA based standard, so this may change in the future.

Most GSM networks are evolving to UMTS..

[jesus_thats_gre]

Apologies about the CDMA Cingular mix up, was getting confused with Verizon...

Anyway...

Off cource Wideband CDMA is better than the narrow band GSM standard. W-CDMA is being used primarly in 3G networks, specifically by NTT in their Foma standard/network in Japan and throughout the whole of Europe in UMTS. GSM is a 2G standard and was first introduced about 15 years ago. W-CDMA based standards were only introduced 3 or 4 years ago in Japan and about a 12 months ago in Europe.... Pretty obvious which is going to be better... Basically, UMTS networks started out as GSM networks while NTT DoCoMo's WCDMA network evolved from PPD/JDC...

The main 3G standard being emlpoyed by CDMA networks in the states and parts of Asia are an evolution of CdmaOne called Cdma2000. This is currently in its 1xRTT mode in most networks and offers speeds of 144kbps while the odd network operate in the upgraded 3xRTT mode which offers better transfer rates of up to 2mbps which is the same as UMTS... GSM in Europe anyway offers 14.4kbps with a single CSD channels, 43.2kbps using HSCDC which uses 3 CSD channels and 40+ kbps using GPRS. Very few networks in Europe have chosen to use Edge, instead electing to skip it and move straight to UMTS.


The basic evoltion of GSM networks is

GSM - GPRS - EDGE - UMTS

The same can be said for TDMA. TDMA based networks are making the move to GSM as both standards are very similar...


Finally there is nearly triple the number of CDMA users in North America compared to GSM.

http://www.cdg.org/worldwide/cdma_world_subscriber.asp

http://www.cellular.co.za/stats/stats-americas.htm


http://www.cellular.co.za/news_2004/Jan/122703-gsm_gaining_ground_in_north_amer.htm

GSM has a long way to go, because there are 71 million North American CDMA phones versus GSM's 22 million.