When consumers think about mobile providersnetworks, their basic requests are related to the quality of services, support, pricing and other factors. When you select a network operator, you also have to choose between a GSM or WCDMA network.
You probably encountered these termsearlier, when they chose a new mobile phone, they first connected to the providers or changed them. But do you know what they mean and what is the difference between them? To make the right choice, you should consider in more detail what distinguishes GSM from WCDMA and which one is better.
GSM выступает в роли Глобальной системы мобильной and is now considered the standard of communication on a global scale, especially in Asia and Europe, with availability in more than 210 countries. It operates on four different frequency bands: 900 MHz and 1800 MHz - in Europe and Asia, and 850 MHz and 1900 MHz in the Americas. The GSM Association is an international organization founded in 1987, which is designed to develop and control the expansion of wireless usage of this standard.
GSM uses TDMA (Multiple Access)time division), which divides the frequency bands into several channels. In this technology, the voice is converted into digital data that is transmitted through the channel and time interval. At the other end, the receiver listens only at the designated time interval, and the call combines both signals. Obviously, this happens in a very short time, and the recipient does not notice the “gap” or time division.
CDMA, or multiple access with codedivision, became a standard developed and patented by Qualcomm, and subsequently used as the basis for CDMA2000 and WCDMA standards for 3G. However, due to its proprietary nature, WCDMA technology has not received such a global implementation that GSM has. Currently, it is used by less than 18% of networks around the world, mainly in the United States, as well as in South Korea and Russia. How does GSM differ from WCDMA from a technical point of view?
В сетях WCDMA цифровые вызовы накладываются друг on each other, assigning unique codes for their differentiation. Each ringing signal is encoded with a different key, and then they are transmitted simultaneously. Each receiver has a unique key capable of dividing the combined signal into its individual calls.
Both standards have multiple access thatmeans that multiple calls can go through the same tower. But, as you can see, the main difference between them is related to how the data is converted into radio waves, which your phone transmits and receives.
The main reason whyTelecom companies had problems with the rapid deployment of the new format, the difference in the frequency ranges they use. Because of this, phones released with only GSM support could not communicate with WCDMA networks, and vice versa. To get around this, most device manufacturers had to apply multiple frequency bands for 2G and 3G networks. This ensured that mobile phones could be used on virtually any network and anywhere in the world.
Before the advent of 4G LTE technology, the obvious difference between GSM and WCDMA devices was associated with the SIM card. GSM phones were supplied with a SIM card connector, but a CDMA device was not.
In other words, WCDMA is a standard based onphone number associated with a specific device that supports 3G. If you want to switch to another phone, you will need to contact the provider, deactivate the old device and activate the new one. On the other hand, in GSM devices, the number is connected to the SIM card, so when switching to another device, all you need to do is place the SIM card in the new phone.
Network coverage is independent of whether it is GSMor WCDMA. What is the difference in this case? This characteristic is more dependent on the infrastructure that the operator has. GSM networks are much more popular around the world, with the exception of the United States, where Verizon Wireless, the (W) CDMA network, boasts the largest number of subscribers in the country.
When connected internally, it doesn't matterwhat kind of network do you use if its coverage is sufficient. So, in Russia you can freely use WCDMA or GSM. What is the difference outside the country?
When it comes to international roaming,GSM has many advantages: there are much more of these networks around the world, as well as a lot of roaming tariffs between these providers. With a GSM phone, you also have the advantage that you can purchase a local SIM card wherever you are (provided that you use an unlocked device). In turn, you will not be able to get full access to the connection to WCDMA data, depending on the device and network compatibility.
With the advent of 4G and the adoption of LTE and LTE-Advanced inAs a standard, most network operators around the world debate about GSM and WCDMA takes less time. Today, you may notice that the latest smartphones designed for WCDMA networks also come with SIM slots to take advantage of the 4G LTE capabilities of the network.
The difference of GSM or WCDMA devices causesthat they cannot be interchanged even now and will never be cross-compatible, but in the near future this will not matter. This is due to the fact that modern developers continue to move towards a full transition to 4G LTE. This technology has obvious advantages.
Так, при международном роуминге главный фактор – This is the quality of a voice call and the satisfaction of 3G user data requirements. These parameters can be equally good in GSM or WCDMA networks. What is the difference? 3G modems built into these devices can exhibit high functionality. But regarding such factors as availability, coverage and price of services, 4G offers the best conditions.
