GSM- Global System For Mobile Communication

GSM - Global System for Mobile Communication

Important from the examination point of view and in general also asked in previous examination of UPSC Prelims

2010 UPSC Prelims and Bank Exam Consider the following 1.     Bluetooth device 2.     Cordless phone 3.     Microwave Owen 4.     Wi-Fi device

Which of the above can operate between 2-4 and 2-5 GHz range of Radio frequency band? 1 and 2 Only 3 and 4 Only 1, 2 and 4 Only 1, 2, 3 and 4

2010 Prelims Which among the following do/does not belong/belongs to the GSM family of wireless technologies?

1.     EDGE 2.     LTE 3.     DSL 4.     Both EDGE and LTE

Introduction

As we are living in this modern world, but no idea how we connected, how the communication channel is establish between individual to individual, knowing small thing will make big difference in understanding the communication channels that exists around us, from the early morning of the day to late night of the day we use mobile phones, Almost it became inseparable part of our body, like our limbs

What we know about the cell/mobile is that, we use it when incoming call comes and dials when requires to contact any one and some chats and applications uses?? Accept it, but most of us don’t know the actual process involved in process of communication, i.e. from staring point when we dial a number on a phone, to the receiver who receives it

This article may bridge the gap to understand a little bit the process of communication involves between mobiles, Have you heard the terms like GSM, CDMA.

Important Terms for all Competitive Exams

GSM: Stands for Global System for Mobile communication

CDMA: Code Division Multiple Access

These both are the technologies used in mobile communication. Most of population around the world uses GSM Mobile technology to communicate between them. Here in this article we learn a few technical details regarding GSM technology

GSM Technology

GSM: GSM Communication system is the network of communication channel by which we communicate through our mobiles

How your Mobile/Cell phone works?

We start with SIM?  What your SIM card contains?

SIM: Stands for subscriber identity module, It contains the information of our authenticity, PUK codes, and some memory to store information of your contacts

One picture says more than 100 words, To understand how the call flow in GSM Mobile communication you must understand the following diagram, at least know the terms specified below and see the diagram it explains almost every aspects and the networks and components involved in the communication process

To understand how the call follows you must at least know what the following terms are

SIM - Subscriber Identity Module

ME - Mobile Equipment

MS - Mobile Station

GSM Mobile Station

If you want till the in depth understanding of the GSM communication see the below diagram, must more emphasized of the above ones see from the SIM in both Diagram and understand the detail of the terms involved in it

• 1    HLR- Home Location Register (HLR)
• 2.     VLR- Visitor Location Register (VLR)
• 3.     EIR- Equipment Identity Register (EIR)
• 4.     AuC- Authentication Center (AuC)
• 5.     SMS SC- SMS Servicing Center (SMS SC)
• 6.     GMSC- Gateway MSC (GMSC)
• 7.     CBC- Chargeback Center (CBC)
• 8.     BSC- Base Station Controller
• 9.     BTS- Base Trans Recevier
• 10 TRAU-Trans coder and Adaptation Unit (TRAU)

GSM Mobile Network

 

How Call Flows in GSM Network

“WHAT IS CALL FLOW IN GSM MOBILE COMMUNICATIONS?”(How the system works when we dial a number)

As soon as the owner switches on his mobile phone, it registers with the network provider via the nearest base station. At the network provider, data on the identity of the user, the serial number of the mobile phone and the identity of the base station over which registration has occurred is logged and stored. This is done even if no conversation takes place. Moreover, every time a number is dial, this event is stored, irrespective of whether a connection is established or not, Mobile user dial a number and press call button at that time first the signal go into the nearest BTS (Base Transceiver Station) transceiver-transmitter and receiver both, Mobile to BTS connection is air interface there is no cable interface between them

BTS is connected with BSC with cable (generally used fiber optics). BSC is the mediator between BTS and MSC-Mobile Switching Center

MSC-heart of any mobile station.MSC is connected with HLR-Home location Register, VLR-Visitor location Register, PSTN-Public switching telephone Network, 

IP-Intelligent Peripheral, Any connection with done during call process MSC is done main job, First VLR check all necessary information of the caller and send it to the HLR, it depend upon the location of caller and receiver, Then check all the system perfect of the caller the call setup between the caller and receiver

Conclusion

GSM, together with other technologies, is part of the evolution of wireless mobile telecommunications that includes

• High-Speed Circuit-Switched Data (HSCSD)
• General Packet Radio System (GPRS)
• Enhanced Data GSM Environment (EDGE)
• Universal Mobile Telecommunications Service (UMTS) 

and thus the connection between our mobiles happen with much faster and simple way by using all this networks.