Anyone with cell phone service in the United States knows that there are four major wireless carriers. Usually, the typical concerns for consumers regarding that service are low prices, great coverage and quality and selection of smartphones. However, there is another aspect of mobile network providers: a choice between a GSM or CDMA network. If you have been with more than one carrier, you may have come across the issue of different network technologies preventing you from using your old phone. Many people don’t know the difference between the two. Here is all the information regarding GSM vs CDMA networks and what it means for consumers.
GSM is the most common technology standard for mobile communications throughout the world. It stands for “Global System for Mobile Communication” and is especially prevalent in Europe and Asia and is available in more than 210 countries across the globe. In general, GSM technology runs on four frequency bands of 900 MHz and 1800 MHz in Europe and Asia and 850 MHz and 1900 MHz in North and South America. In 1987, an international organization called the GSM Association was founded for the purposes of developing and overseeing the expansion of the GSM wireless standard.
In addition, there is a specific variant that GSM technology used known as TDMA or time division multiple access. It helps to divide the GSM frequency bands into a variety of channels. GSM technology allows a mobile phone user’s voice to be transformed into digital data that is designated to a specific time slot and channel thanks to TDMA. At the other end of a phone call, the receiver can only listen to that time slot with the call being pieced together. In other words, there is a break within the time division that occurs, but it happens in such a minute amount of time that the receiver doesn’t even notice it. You can compare GSM cell phone plans using Wirefly's comparison tool.
CDMA technology was developed and patented by Qualcomm, a famous chip maker. It stands for code division multiple access and is used for the standards of 3G that include CDMA2000 and WCDMA. It is proprietary in nature, which has resulted in the technology not being adopted globally in the manner in which GSM has seen. At this point in time, fewer than 18 percent of wireless networks around the world use CDMA technology. It is mostly found in the US within two of the four major wireless carriers, Sprint and Verizon Wireless. There are other countries that also use it, specifically Japan, South Korea and Russia.
The way CDMA networks perform is that calls digitalized over one another and a unique code is given to each for the purposes of differentiating them. Each set of data for every call is given a different key and calls are transmitted simultaneously. When someone makes a call using a CDMA phone on a CDMA network, the receiver will also get a unique key so that the combined signal can be split apart into an individual call. You can compare CDMA cell phone plans using Wirefly's comparison tool.
Both GSM and CDMA standards get multiple access, meaning that a large number of calls can go through a single cell phone tower. However, the one chief difference between the two standards involves the way the data is transformed through the radio waves a smartphone receives and broadcasts. Of course, there are a variety of reasons why you might want to opt for one technology standard over the other. Here are the most practical reasons why you would choose GSM over CDMA or vice versa:
Previously, before 4G LTE connectivity was created, the one big difference between GSM and CDMA phones had everything to do with SIM cards. GSM phones always included a SIM card slot and CDMA cell phones lacked them. In general, this means that CDMA is a standard for handsets, along with a phone number assigned for a particular phone. If a user wished to upgrade to a new cell phone, it meant contacting the carrier through its customer service line and having their old phone deactivated. The new phone had to be activated through the wireless carrier. However, with GSM cell phones, the phone number is assigned to the SIM card instead of the phone. In other words, if you want to get a new device, the only thing necessary is to remove your SIM card from your old phone and put it into the new one. The only exception to this rule is if you decide to switch to a different carrier. For example, if you were an AT&T customer and had a phone locked to the carrier but left to join T-Mobile and your old phone is locked to AT&T, you would not be able to use it on your new carrier.
The coverage offered by a wireless carrier doesn’t depend on the standard it uses but on the infrastructure it has built. GSM networks are more popular overall, but in the US, Verizon has the greatest number of subscribers.
International Roaming: GSM has the advantage when it comes to international roaming. Because it is the dominant standard globally, if you have a GSM phone that is unlocked, you can use it with any SIM card in any country that uses GSM technology. That means if you are a frequent traveler, being on a GSM network with an unlocked smartphone allows you to buy a SIM card wherever you are and pop it in to use your phone in that country.
The current standard of LTE and the emergence of LTE-Advanced means it definitely matters whether you use a GSM or CDMA network. Many of the latest CDMA phones are now equipped with SIM card slots so that they can get 4G LTE. Generally, both standards are excellent for voice calls, but when you choose a carrier, you have to consider other aspects as well.
