What Is CDMA And How Is It Different From GSM?


Do you know what is CDMA? CDMA stands for Code Division Multiple Access. This is an international standard that provides cell phone service technology.

What Is CDMA?

CDMA competes with GSM, however, GSM is used much more throughout the world. Many of the cell phones that are currently on the market are either CDMA phones or GSM phones.


CDMA and GSM are not compatible, CDMA phones can only be used with cell phone carriers that use the CDMA networks. The same is true for GSM phones.


However, if you have an unlocked phone, then it’s compatible with both networks and it can be used with any carrier you choose.

What Networks Use CDMA Or GSM?


In the U.S. we use CDMA and GSM, Verizon and Sprint use CDMA while AT&T and T-Mobile use GSM.


CDMA vs GSM Which Network Is Better?


CDMA vs GSM Which Network Is Better?

For the most part, you should not be concerned about which network is better because they provide the same service in terms of bandwidth speed.


However, GSM offers more global coverage as a result of roaming and international-roaming contracts.


GSM networks also do a better job covering the rural areas in the U.S. in comparison to CDMA.


Changing Your Phone:


If you’re due for an upgrade, it’s much easier to change your phone if your phone is on the GSM network in comparison to the CDMA network.


GSM phones use removable SIM cards to store the user’s data on the GSM network.

SIM Card
SIM Card


While most CDMA phones do not have SIM cards. CDMA carriers use data on the carrier’s server to verify the same data that GSM phones store on their SIM cards.


As a result of this, the SIM cards in the GSM phones are interchangeable so this gives you the ability to remove the SIM card from one GSM phone and put it into another GSM phone while keeping the same phone number.


This gives you the ability to use an AT&T phone on the T-Mobile network and vice versa.


Transitioning from one CDMA phone to another isn’t so simple because most of them don’t have SIM cards and you need permission from your carrier.


There are some CDMA phones which use SIM cards but they do this because the phone has a slot for a SIM card or because the LTE standard requires it.


But these SIM cards work differently because the carrier still uses CDMA technology to store your private data.


You’re probably wondering why do Verizon and Sprint use CDMA technology? In 1995 and 1996 Verizon and Sprint switched from analog to digital.


At that time CDMA was the fastest, newest technology available. It offered better call quality, greater capacity, and more potential than the GSM networks that we have today.


Over time GSM caught up but there was no turning back for Verizon and Sprint by that time.


Data And Voice Usage On CDMA Networks:


On most CDMA networks you will not have simultaneous data and voice transmissions.


As a result of this, you will not receive any notifications while you’re talking on the phone because your data is on hold. You will receive your notifications after the call has ended.


However, if you’re connected to a Wi-Fi network then two-way data exchange will work just fine on a CDMA network. This is possible because Wi-Fi isn’t using your carrier’s network.


Now You Know What Is CDMA:


If you have any comments or questions about any of this information, please feel free to share them in the comment section below.



  1. Hello, My name is Pedro and, lately I have a little problem, My carrier is cricket and as of January 2021 they are forbidding cellphones that they think are older than 4G that in fact are more than capable to get it, like my oneplus 7 pro and I’m trying to find a way to disable 3g on my cellphone, looks like by punching #*#*4636*#
    and choosing the right channels I could do this but I lack the Knowledge to choose the right combo, could you pretty please lend me a hand?, I’m sure that many people will be looking for a solution for this problem since cricket just did this and frankly is the stupidest thing since they won’t retire 3G till 2022 and the logic way would be to just let the hardware drop the service not the provider cancel the SIM!, Thank You and waiting for your answer!

    • Hello Pedro,

      I’m sorry to hear about the problem that you’re having, however, I did some research on the code #*#*4636*# that you used and I discovered that this code may be used to select what network you would like to use but the problem is, that it doesn’t work on all phones. If you can’t get this to work you should consider switching to a new carrier.


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