What is the difference between CDMA and GSM Phones?

Question

In Phone mode of transmission and which is superior?

Answer 1

They're different kind of technologies in the cell phone industry. GSM phones, are the phones with the SIM cards (which you can buy @ Cingular, Altell, TMobile, Cell One) CDMA are your Verizon & Sprint phones.

I've sold GSM & I've used both...I like CDMA the best (it works better in Toledo, OH), but GSM works in areas that CDMA doesn't (like where I grew up). If you travel overseas, you should get a GSM phone, b/c you can buy a temporary SIM card over there & your phone will work...unlik CDMA. It really depends on where you live & what works the best...ask around or ask the cell phone carrier to show you a coverage map of where you live, work, etc. to see if that service is going to work best for you.

Answer 2

One of the basic things that differentiates GSM (based on TDMA) and CDMA is the way the carve up bandwidth.
Each bit of radio spectrum used by a handset has to be shared with other people in the area. It is more or less the same as multiplexing for normal data land lines.
The major difference between GSM/TDMA and CDMA is in the way they divide up those signals between multiple users.
GSM/TDMA uses a Time Division method. TDMA, in fact, stands for Time Division Multiple Access. Simply put, this means that each device on the local network is allocated a time slice where it "owns" the bandwidth, and it can send/receive its data.
So lets just pick a number and say there are 30 available time slices in a given cycle. Each phone would then get 1/30th of every cycle that it could send and receive data (aka, voice).
CDMA uses a different method, called Code Division Multiple Access. The specifics of how it breaks the cycle up are beyond me, but how it works out is that the phones only get a slice of the bandwidth cycle when they actually need one. So if you are not talking, and the other person is not talking, nothing is transmitted.
With GSM/TDMA, each phone is transmitting and receiving during its slices of the bandwidth cycle, whether it needs it or not.
Since most coversations are comprised largely of silence, the end result is that CDMA phones have to transmit less data. They don't have to send silence, like GSM/TDMA phones do.
This means a few things. More CDMA calls can be fit into a given amount of frequency spectrum (ie. it is more efficient for the network), less radiation is being created from the phone towards the user (you only get radiation when you are talking, basically), and battery power is conserved since the handset only transmits when it actually has something to send.

Answer 3

1. Code Division Multiple Access or CDMA is the the technique were the signal is shared equally by other mobiles, in CDMA the voice is Superior due to large bandwith

2. Gobal Switch Modulation is GSM were the frequency is switched according to the call, and the carrier strength is high, bou the voice clarity is low.

Most world mobiles operate in GSM and most US/Canada/Taiwan/Korea and Japanese mobiles operate in CDMA.

In regard to transmission and VAS like internet, frequency penetration, flexibile netword etc are with GSM only. There is another type of mobile service called TDMA : Time division multiple access, used in Satellite phones, where the carrier is released only for the time of the call and not always and the spectram is shared only on time used for the call.

Answer 4

Code Division Multiple Access, a method of encoding and carrying digital cellphone messages which is commonly used in America and elsewhere. It rivals GSM in other countries (particularly Europe) as the standard for digital cellular. In New Zealand, Telecom's mobile service is based on CDMA, while Vodafone runs on GSM. Variants of CDMA that will be used in high-speed cellphone data services include W-CDMA and cdma2000.

Global System for Mobile communications, the most widely used digital mobile phone system and the de facto wireless telephone standard in Europe. Originally defined as a pan-European open standard for a digital cellular telephone network to support voice, data, text messaging and cross-border roaming. GSM is now one of the world's main 2G digital wireless standards.