GSM | CDMA | LTE - All you need to know

The CDMA, GSM and LTE are the networks on which Mobile companies which provide services. These are wireless networks that are required for any kind of Mobile network communicaton. In this article, we are going to focus on the three types of wireless networks and discuss them in depth.

GSM (3G)

The first cellular technology that we are going to discuss here is, GSM, often referred to as Global System for Mobile Communications. Along with most Mobile operators throughout the world, in India we have Airtel, Reliance, Vodafone and BSNL as top carriers that use GSM as the backbone. On a GSM Network, a user's phone number and their voice, text and data plans are programmed into a small chip called a SIM Card or Subscriber Identity Module. Since your wireless services are tied only to a SIM Card with GSM, you can easily move your services to a new phone optimized for the same cellular service just by inserting your SIM Card into your new device. This is helpful if you break your existing device or you want to travel international with an unlocked phone.

CDMA or Code Division Multiple Access

CDMA was created by Qualcomm, the same company who makes CPUs for an overwhelming majority of the android phones sold in India. For most of them, CDMA is the network offered by MTS India, Reliance and TATA Indicom in India. The key thing that maked CDMA different from GSM is that CDMA does not involve the use of SIM Cards instead CDMA carriers like MTS India or Reliance, they have a list of codes called ESNs or Electronic Serial Numbers. This list identifies particular handsets that can be used on a given CDMA network. Now, if your phone does not have a code that is listed on a given carriers network, you simply cannot use that device on a carrier like MTS India. So, instead of emedding your subscriber information onto a SIM, with the CDMA-based carrier, your voice plan, texting plan and your data plan, it's all embedded in the actual phone itself.

Strengths and weaknesses of GSM and CDMA

As mentioned earlier, GSM allows you to move your services from one device to another through the simple use of a SIM Card. In addition to that, GSM devices can also transmit voice calls and use data at the same time whereas 3g CDMA devices cannot. Now, if you have an old GSM SIM device lying around that hasn't had service in a while and you want to reactivate it. An important thing to note about GSM devices is, if a SIM Card goes for a certain period of time without service, it's usually 3-4 months here in India, you'll lose the phone number that was associated with that SIM Card and also the SIM Card itself is going to expire. On the other hand, to reactivate a CDMA device, all you have to do is dial a simple into the dialer. Lastly, the main disadvantage of CDMA in comparison to the GSM is that CDMA devices cannot easily be transferred from one mobile operator to another.

LTE (4G)

Most of you reading this article on your phone on Reliance or any other carrier network, you notice that you phone does have a SIM Card, that's most likely because you are using an LTE enabled 4G device. All of the national wireless carriers have been expanding their LTE or Long Term Evolution networks for the past few years. The reason why you hear the carrier's talk about LTE so much is that LTE is the fastest cellular data connectivilty thats available right now. If for some reason your phone disconects from the LTE network, your phone will then use CDMA as a fallback. Over the past several years, most smartphones have had both a voice connection and a data connection built in. More recent, you have heard something called Voice over LTE.

Basically, what Voice over LTE is, instead of having both a voice connection and a data connection to the network, your phone will process both data and phone calls over the same connection. This benefits CDMA LTE based customers in the sense that, they can now talk to other people and use data all at the same time.

Sometimes, if you are in a place with limited service or if your carrier's throttling your data speed, you might see an 'E' next to your signal bars, if you have a GSM device. The 'E' stands for an Informative of 2g knoen as Edge. The 2g standard brought us the ability to access the Internet over cellular as well as the first modern smartphones like the blackberries and the iPhone. In terms with speed, 2g is often equated with dial-up internet. For those of you, who have a CDMA device you might see a from of 2g called 1x displayed on your device.

Conclusion

Overall, GSM and LTE are the most common forms of cellular connectivity in use today along with the CDMA in India and a handful of other countries.