CDMA vs GSM - What's the Difference?

We explain the difference between GSM and CDMA


Shopping for mobile phones can be confusing due to the many acronyms associated with them. By understanding what these acronyms mean, it can make the shopping process less confusing while explaining why mobile phones from one carrier are not compatible with another.

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Two of the most common acronyms you'll come across while shopping for smartphones are GSM and CDMA. These represent the basic technologies found in phones. However, these technologies differ in many ways.

CDMA vs GSM - What's the Difference?

What is GSM?

GSM stands for Global System for Mobiles and is a radio system used in mobile devices. TechTarget states that of the three major wireless technologies available, GSM is the most widely-used especially in areas like Europe, though you'll find several major carriers in the United States that uses the network too.

The appeal to GSM rests in its capability. Since its network expands around the world, its roaming capabilities are better, resulting in your GSM phone having better access for international calls. Because of the extensive size of the network, it is also a great option in rural areas.

Another benefit of GSM is its versatility. In the United States, GSM phones use SIM (Subscriber Identity Module) cards. You can think of your SIM card as your phone's driver's license in that it represents your digital identity. The appeal to SIM cards is you can transition easily between GSM phones. All you have to do is to take out the SIM card and insert it into the slot of your new GSM phone. Your new phone recognizes your number, contacts, and other information stored on the card.

What is CDMA?

CDMA stands for Code Division Multiple Access. CDMA represents multiplexing between numerous signals for optimal bandwidth availability. Along with this, CDMA networks employ a soft handoff scheme that keeps signal breakup during transfer from one headset to another to a minimum.

CDMA doesn't offer the same versatility concerning its phones the way GSM does. The reason for this is CDMA providers verify their customers through network-based white lists, according to PC Mag. This means if you have a CDMA phone, you cannot switch to a new phone without approval from your carrier. This can be problematic if you want to transfer service from one provider to another and want to keep your phone.

what is CDMA?

What's the difference between CDMA and GSM?

Along with the difference in the ability to transfer service between phones, there are inherent differences in the technologies of the two systems. With 3G GSM networks, your phone has the ability to make calls and transmit data concurrently. Meanwhile, 3G CDMA networks don't have the capability of doing multiple tasks such as transmitting data while making calls at once.

Another difference between the systems pertains to how each process calls. GSM networks use a time division system. How this works is when you place a call, the network assigns a time slot and channel to your data.

Conversely, CDMA networks use code division. With this data from a call comes with a specific key and transmits together, making this method more versatile.

At the same time, CDMA lags behind GSM in speed. Currently, CDMA networks have speeds of up to 3.6 Mbps. GSM networks have far surpassed this thanks in part to the HSPA extension, giving the network's capacity speed of up to 42 Mbps.

The Future is 4G LTE

As you might have noticed when shopping around, all four of the major carriers tout they offer 4G LTE fast networks. It's important to note that 4G and LTE are not the same things. LTE is named after the technological advancements made from networks moving from 3G to 4G. In the case of 4G, it has become the standard for all wireless networks moving forward. You can research the best cell phone plans to find the most appropriate service for you.

What's more, just because all the carriers have this capacity won't translate into phones being universal in that you can use the same device to transfer service providers easily. The reason for this is each cell phone company uses different frequency bands. Therefore, the limitations of switching services found on CDMA networks still exists in the land of 4G LTE.

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Q Is Verizon GSM or CDMA?


Verizon uses CDMA.



AT&T uses GSM.

Q Is T-Mobile GSM or CDMA?


T-Mobile uses GSM.

Q Is Sprint GSM or CDMA?


Sprint uses CDMA.

Q What does it mean when a phone is GSM?


Simply, it means the phone uses the GSM network. Providers like T-Mobile and AT&T use this network. Moreover, with GSM networks, you receive greater flexibility with your device. With GSM phones, you receive a SIM card that represents your digital identity. To transfer service from one GSM phone to the next, simply take out the SIM card and insert it into the new phone.

Q What is the CDMA network?


A CDMA network is one of three major networks found worldwide carriers use. In the United States, carriers like Sprint and Verizon use the CDMA network. This network transmits data through code division, making it the most powerful and flexible offering available. The results of this include less signal interruption during a call.

There are limitations to using this network, though. For one, because advancements haven't been as pronounced as GSM has been, the CDMA network is slower than GSM. Furthermore, CDMA uses white lists to verify their customers' information. This means if you want to switch service providers or phones under the CDMA network, you must receive permission from your carrier before doing so.

Q What is a GSM phone carrier?


It is a carrier that uses the GSM network. Examples of this include companies like AT&T and T-Mobile. Since GSM is the most commonly used network worldwide, it translates into better reliability in remote areas. Along with network capabilities, a phone carrier's plan offerings are important to consider.

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