What is GSM?
GSM - Global System for Mobile communication.
It is a commonly used wireless Technology for mobile communication.
It is a digital system that works on the TDMA technology.
It is called as Groupe Special Mobile.
What is that TDMA?
TDMA means Time Division Multiple Access.
The data that we are transmitting from various sources have to travel in a single channel to reach the corresponding destination.
In that channel there is more chance of data collision.
To avoid that, the data from each source is allotted with some time slot and then send in the same channel.
So that there is no chance of collision since it allotted with different time slots.
Because of the division of time in a channel it is called as Time Division multiple Access.
How GSM works?
In the transmitting side, the signal/data are encoded, time divided and then transmitted.
In the receiving side, the time divided data are recovered, decoded and then processed.
It operates on 850MHz, 900MHz, 1800MHz and 1900MHz frequency bands.
SIM card(Subscriber Identity Module) plays main role in GSM. SIM is used to identify the user's account.
Roaming is the ability to use your GSM phone number in another GSM network.