# Please tell me difference between CDMA and GSM ..



## Tech_hungry (Jan 8, 2005)

I just want to know the basic difference between gsm and cdma technology?I want to know the whole details.Pls help me out anyone.


Edited Batty


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## alib_i (Jan 8, 2005)

hi tech_hungry ..
firstly welcome to the forum ..

secondly .. 
plz keep a better topic name ..
so that you attract the right ppl to your thread ..

lastly
try any of these links
*www.nokia.com/nokia/0,,42853,00.html
*www.cellularfone.us/resources/cellular_access_technologies.php
*corky.net/2600/mobile-telephony/gsm.shtml

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alibi


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## khandu (Jan 9, 2005)

Wanted to know 1 thing

Take an example of Nokia 7600

it has something called WCDMA and GSM.. So what does WCDMA mean? Can i use that phone and get a Reliance Number on it?? so is that a CDMA + a GSM phone ?


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## Nemesis (Jan 9, 2005)

the W in WCDMA stands 4 "wide"
WCDMA is a technology used in places like south korea...i dont think reliance uses WCDMA so i guess it wont work with phones like 7600, 6650 or the new 6630...and yeah, these phones can work literally everywhere with switching between GSM and WCDMA as easy as the flick of a switch....


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## beyondthegracefgod (Jan 9, 2005)

WCDMA(Wideband Code Division Multiple Access) is  a newer tech (in india) which can be used for data transfer.It is some wat similar to EDGE OR GPRS.
 WCDMA uses the giga hertz range of freq to transfe rthe data which makes it faster.These are just used for streaming movies  which is faster using EDGE or WCDMA rather than using GPRS which uses the radio frequency.
   WCDMA can transfer data at speeds of 384 Kbps to 2 Mbps.
CDMA,TDMA and GSM(which is developed on lines of TDMA) are different networks while EDGE GPRS WCDMA can be used in GSM. 
 GSM stsndards is more versatile due to the provision of Over the air (OTA) configuration .Thats the reason why u can use a SIM card in GSM phones and  
u have to preinstall the stuff in CDMA

REf this book for infoon wcdma:
*www.althosbooks.com/intowc.html


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## drgrudge (Jan 9, 2005)

nemisis said:
			
		

> these phones can work literally everywhere with switching between GSM and WCDMA as easy as the flick of a switch....


Even Japan's DoCoMo offers this type of tech switching thing.



			
				khandu said:
			
		

> So what does WCDMA mean?


This all depends on multiplexing issues. 
Three types:
Time division multiplexing
frequency division multiplexing
wave division multiplexing

TIme division is actually now divided into* TIME divsion multiple access(TDMA) and FREQUENCY divsion multiple access(FDMA).*

Now TDMA is divided into CDMA (code division multiple access). WCDMA is WIDE CODE divition multiple access. More BW is accomodated with wider range of freq of operation.  




			
				Tech_hungry said:
			
		

> I just want to know the basic difference between gsm and cdma technology?


It is just a different tech being used. I can try and explain with a help of example. 

Consider a 10 subscribers who want to get connected with other person. (either same network or different)

*CDMA: *All the ten subscribers are placed in a single room, and their *voice signal is encrypted, so that it isnt decrypted by unauthorised persons or the wrong subscriber. * The decryption is done the person who actually receives the call. 

*GSM:*The ten subscribers are placed in defferent rooms and only the person who calls and the person who receives the call will be in that particular room. Privacy issues are less here. 

Remember the call intrution in case of reliance phone early on when they launched? 

CDMA actually oofers a comparitely cheaper network access. *And also the voice clarity will be marginal better (the signal is decryped and amplified so the clarity will be bound to be good). *

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All this info, tnx to our subject on mobile technology!


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## escape7 (Jan 11, 2005)

In GSM every user is assigned a particular frequency (a SIM takes care of that), In CDMA the signal is brodcasted over a range and the cell collects all that etc.(Thats what i know).


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## Tech.Masti (Jan 30, 2009)

Whats this? You just digged up 4 years old thread.


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## Kniwor (Jan 30, 2009)

Well we dont need any more spam here. Closing Thread.


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