Full Form of GSM

GSM or Global System for Mobile Communication is an open and digital cellular technology used for mobile communication.

What is GSM?

Global System for Mobile communication (GSM) is the acronym for this system. It is a standard produced by the European Telecommunication Standards Institute (ETSI) to describe protocols for digital cellular networks of the second generation (2G). It replaced cellular networks of the first generation (1G). GSM was inspired by a cell-based mobile radio system developed at Bell Laboratories in the early 1970s.

GSM is a global, open, digital cellular radio network that operates in more than 200 countries. It employs time division multiple access (TDMA) technology with a restricted bandwidth. It encompasses nearly all of Western Europe and is expanding in North America and Asia. In addition to voice communications, it can also be utilised for data processing and text messaging. A user can connect his GSM-enabled phone to his laptop in order to send and receive e-mails, faxes, surf the internet, and check security, among other things.

An open and digital cellular technology used for mobile communication, GSM uses four different types of frequency bands: 1900 MHz, 1800 MHz, 900 MHz, and 850 MHz. It uses the combination of TDMA and FDMA.

There are 4 different types of cells used in GSM:

1. Macro: Here, the Base Station antenna is installed.
2. Micro: The antenna height here is less than the average roof level.
3. Pico: Small cells’ diameter of a few meters.
4. Umbrella: The shadowed (Fill the gaps between cells) regions are covered by it.

GSM: History

An initiative had been taken to develop a European standard for digital cellular voice telecommunications when the European Conference of Postal and Telecommunications Administrations (CEPT) set up the Groupe Spécial Mobile (GSM) committee in 1983. They later provided a permanent technical-support group based in Paris. In Copenhagen (1987), 5 years later, 15 representatives from 13 European countries signed a memorandum of understanding to develop and deploy a common cellular telephone system across Europe, and EU rules were passed to make GSM a mandatory standard. Eventually, this resulted in a unified, open, standard-based network which was larger than that in the United States.

The same year, in the month of February, Europe produced the first agreed GSM Technical Specification. Political support for GSM was cemented by the ministers from the 4 big EU countries with the Bonn Declaration on Global Information Networks in May and the GSM MoU was tabled for signature in September. Operators from all across Europe were drawn in to pledge to invest in new GSM networks by the MoU to an ambitious common date.

It was in this short period of 38 weeks that the whole of Europe (countries and industries) had been brought behind GSM in a rare unity and speed. Today, the GSM (2G) has developed into 3G, 4G and 5G.

GSM Enhancements

In 1991, work was in progress for expanding the GSM standard to the 1800 MHz frequency band. It only became possible in the UK by 1993, called DCS 1800. It was also the year when Telstra became the 1st network operator to deploy a GSM network outside Europe and also the 1st practical hand-held GSM mobile phone was made available.

Then in 1995, the commercial launch of fax, data and SMS messaging services, using the 1900 MHz GSM network, meant that the GSM subscribers worldwide exceeded 10 million. It was the same year when the GSM Association was formed. In 1996, pre-paid GSM SIM cards were launched and worldwide GSM subscribers passed 100 million in 1998.

The first commercial GPRS or General Packet Radio Service was launched in the year 2000, and the first GPRS-compatible handsets became available for sale. Then the MMS or Multimedia Messaging System was introduced in 2002, and the first GSM network in the 800 MHz frequency band became operational. In 2003, GSM launched the Enhanced Data rates for GSM Evolution (EDGE) services and the number of worldwide GSM subscribers exceeded 1 billion in 2004.

More than 75% of the worldwide cellular network market was covered with GSM networks by 2005, which served 1.5 billion subscribers. After this, the HSDPA-capable network became operational in 2005. This was followed by the arrival of the HSPA or the High-Speed Packet Access and gradually, the fast internet services of today came into prominence.

Features of GSM

1. GSM supports international roaming.
2. The voice clarity on GSM is very good.
3. GSM can support multiple handheld devices.
4. Spectral / frequency efficiency
5. Low-powered handheld devices.
6. Case of accessing the network
7. It is compatible with International ISDN.

GSM: Architecture and Functionality

GSM is further divided into 3 subsystems:

1. BSS: Short for Base Station Subsystem, it handles traffic and signalling between a mobile phone and the network switching subsystem.
2. NSS: Short for Network and Switching Subsystem, it is the core network of GSM. It carries out the call and mobility management functions for the phones that are present in the network.
3. OSS: Short for Operating Subsystem, it is a functional entity where the network operator monitors and controls the system. Its main purpose is to offer the customer cost-effective support for all GSM-related maintenance services.

These 3 subsystems: BSS, NSS and OSS are connected with each other via some interfaces. These are the 3 interfaces:

1. Air Interface: Also known as UM interface, it is the interface between MS and BTS. It is called so because of the mobile analogue to the U interface of ISDN.
2. Abis Interface: This BSS internal interface links with BSC and BTS.
3. A interface: This information makes communication possible between BSS and MSC.

Therefore, this is the complete architecture and functionalities of the components of GSM.