What is the difference between CDMA and GSM? In the type of separation. GSM uses time and frequency separation, and CDMA uses code division, which gives rise to a number of advantages. Moreover, they relate to both the user and the operator. Now we will figure out what is the difference between CDMA and GSM types.
The main differences
GSM phones use time and frequency separation. A small frequency band is created for each subscriber. In this case, the "procedure" of data exchange is temporary. The signal is interrupted, but due to the high speed of data exchange it is imperceptible. Interruptions can be noticed by a squeak from the phone when it is next to another device.
CDMA uses more advanced code division. Each subscriber is connected to the base station. It uses the entire frequency resource, which is available to all subscribers, and the station communicates immediately with everyone. A call or message from a specific subscriber is allocated using a code: each subscriber has a unique code, which makes him stand out from other subscribers. These methods of connecting subscribers can be described with one simple example. Let's say that there are several people in the room. The first part of people speaks alternately, for 10 seconds - this is the GSM type. The second part speaks out of turn, all at once, but each couple speaks their own language - this is CDMA. In both cases, people can communicate, but out of turn communication in 10 seconds is much more comfortable.
Who has more benefits
The difference lies in the wider frequency band. For the subscriber, the benefits are:
- better data transfer quality: a large separately leased line is more stable;
- safety: the intercepted CDMA signal looks like noise, it is almost impossible to select a subscriber and hear a voice;
- lower power consumption of the communication device: the signal in the CDMA network is less powerful compared to GSM and depends on the distance to the repeater.
The advantage of CDMA for operators is a larger number of stations, and hence their larger radius, as well as easier network setup and protection against overloads. CDMA operators can cover a much larger area with minimal equipment costs, unlike GSM.
Then the question arises: "Why is the GSM format more common if CDMA is better in everything?" There are not many reasons, and they are simple. When they created CDMA, GSM already existed. In the event of a transition, there was a problem with consumer equipment and equipment for operators. Because of its features, CDMA required more powerful computing power, since the separation was code-based and each subscriber had to be processed. Funding was also needed to develop a less common network, and phones with CDMA support are more expensive.
In addition, there was a problem in user convenience. In a GSM network, a subscriber can be identified by a physical SIM card (it stores information that the operator needs). If the user wanted to change the phone to a new one, he just needed to rearrange the SIM card, and there was no need to notify the operator about this.
There are no SIM card slots in CDMA phones; the information required by the operator is flashed into the phone itself. Because of this, in order to change the phone, you need to carry it to the communication salon. Also, a CDMA phone cannot be used in roaming. Today, there are already phones that can simultaneously support two network formats; the problem of a limited selection of devices has been resolved. American operators have become the engine of this progress, they have made the biggest contribution to this technology. Within the Russian market, CDMA operators occupy a much smaller share, the choice of compatible smartphones or phones is less, but if desired, the user can buy the device on the international market.
Given the pros and cons, the choice of network type depends only on the coverage of a particular territory by your operator. The main difference between CDMA and GSM is the presence of a physical card.
How to distinguish CDMA from GSM?
As we have already found out, the difference between CDMA and GSM is the lack of a physical SIM slot.
- If your phone has a SIM card, most likely your phone uses GSM networks, if your device does not have a SIM card tray, most likely you have a CDMA phone.
- By mobile operator.
GSM phones use a SIM card, CDMA - E-Sim.
How to determine the type of connection on the iPhone?
You can distinguish between GSM or CDMA iPhone by the number on the back cover.
iPhone 5s and later use LTE. How to find out the type of connection on previous devices?
iPhone 5c:
- A1532, A1507 or A1529 - iPhone 5c GSM;
- A1532 or A1456 - iPhone 5c CDMA;
- A1516, A1526 or A1529 - iPhone 5c GSM, China.
iPhone 5:
- A1428 - iPhone 5 GSM;
- A1429 - iPhone 5 GSM and CDMA;
- A1442 - iPhone 5 CDMA, China.
iPhone 4s:
- A1431 - iPhone 4s GSM, China;
- A1387 - iPhone 4s CDMA;
- A1387 - iPhone 4s GSM.
iPhone 4:
- A1349 - CDMA iPhone 4s;
- A1332 - iPhone 4 GSM.
iPhone 3Gs:
- A1325 - iPhone 3GS;
- A1303 - iPhone 3GS.
iPhone 3G:
- A1324 - iPhone 3G;
- A1241 - iPhone 3G.
iPhone uses only 2g format.
On iPhone, what is the difference between CDMA and GSM? In Russia there is no support for E-Sim, and therefore the iPhone, released to the Russian market, does not support this technology. In the rest of the world, you can choose the type of connection, CDMA or GSM, when purchasing.