Our technology

Our technology

Find out about the GSM family of technologies and their important role in providing mobile communications for all, from the 1990s until the present day. 

The GSM family of technologies

The GSM family of technologies provides the world with mobile communications. The original GSM technology in 1991 was developed due to a need for the unity necessary between businesses and countries to enable pan-region, digital, mobile voice calls.

Thanks to GSM’s common standard and unification, the first global networks could emerge, along with GSM Roaming and its convenience for travellers – a key driver behind the global success of the GSM Platform. 

This commonality, along with GSM’s continual enhancement, has paved the way for the mobile broadband and multimedia services we see today.

Here you can find out more about the GSM family of technologies and how it has evolved over time to meet innovation, as well as growing demand.

GSM – used in 219 countries and territories

What does GSM enable?

GSM serves more than five billion people, providing travellers with access to mobile services, wherever they go.

The technology’s international roaming capability, along with the use of harmonised spectrum across most of the globe, allows travellers to access the same mobile services at home and abroad. With GSM, you can use the same mobile number to reach someone, in up to 219 countries.

What is it?

GSM (Global System for Mobile communications) is an open, digital cellular technology used for transmitting mobile voice and data services.

Terrestrial GSM networks cover more than 90% of the world’s population. While GSM satellite roaming extends service access to areas where terrestrial coverage is not available.

Useful technical information

  • GSM supports voice calls, data transfer speeds of up to 9.6 kbps and the transmission of SMS (Short Message Service)
  • GSM operates in the 900MHz and 1.8GHz bands in Europe and the 1.9GHz and 850MHz bands in the US
  • GSM services are also transmitted via 850MHz spectrum in Australia, Canada and many Latin American countries

GPRS – for data services, such as social networking

What does GPRS enable?

Feature-rich data services, such as email on the move, multimedia messages, social networking and location-based services.

With its throughput rates of up to 40 kbps, mobile handsets can access online services at a similar speed to a dial-up modem, but with the convenience of connecting from almost anywhere.

What is it?

GPRS (General Packet Radio Service) is a very widely-deployed wireless data service that’s available with most GSM networks.

EDGE – three times more data capacity than GPRS

What does EDGE enable?

The delivery of more demanding mobile services, such as the downloading of video and music clips, multimedia messaging and full web browsing.

Using EDGE, operators can handle three times more subscribers than GPRS, triple their data rate per subscriber or add extra capacity to their voice communications.

What is it?

Enhanced Data rates for GSM Evolution (EDGE) technology provides up to three times the data capacity of GPRS. It can be overlaid directly onto an existing GSM network, as it uses the same structure. 

Due to the low cost of including EDGE in a GSM network deployment, almost all GSM infrastructure is EDGE capable.

3G/WCDMA – delivers richer mobile multimedia services

What does WCDMA enable?

Richer mobile multimedia services such as music-on-demand, TV and video streaming, as well as broadband internet access.

What is it?

Developed by the global GSM community to support third-generation (3G) mobile services, WCDMA is Wideband Code Division Multiple Access technology and can carry data at high speeds – as well as support conventional voice, text and MMS services.

HSPA – supports both voice and mobile broadband data services

What does HSPA enable?

Upgrades 3G/WCDMA networks, so they run at broadband speeds. Unlike many other mobile broadband technologies, HSPA supports the very efficient provision of voice services in combination with mobile broadband data services.

What is it?

Standardised by 3GPP, HSPA is a set of technologies including HSDPA (High Speed Downlink Packet Access), HSUPA (High Speed Uplink Packet Access) and HSPA+.

Useful technical information

  • In most HSPA networks, the end-user can expect throughput speeds of at least 1 Mbps, with actual performance varying according to local conditions 
  • Peak downlink speed of the network can reach 14.4 Mbps
  • Peak uplink speed can reach 5.7 Mbps


HSPA+ networks run at even faster speeds, theoretically reaching peak data rates of up to 42Mbps, by harnessing MIMO (Multiple-Input, Multiple-Output) capabilities and higher order modulation (64QAM) techniques.

LTE – very fast data speeds for 3G and 4G

What does LTE enable?

Very fast data speeds for 3G. Up to 100Mbps in the downlink and 50Mbps in the uplink – depending on the spectrum available.

What is it?

Long Term Evolution (LTE) is a mobile network technology deployed by mobile operators on both the GSM and the CDMA technology paths. It’s designed to be backwards-compatible with GSM and HSPA, so mobile operators can provide a seamless service across LTE and existing deployed networks.

Useful technical information

  • Provides high levels of spectral efficiency and network performance, coupled with high network capacity and low latency. 
  • Since it incorporates Multiple In Multiple Out (MIMO) technology, the Orthogonal Frequency Division Multiple Access (OFDMA) air interface in the downlink and Single Carrier FDMA in the uplink. 
  • LTE will support spectrum channel bandwidths from 1.4 MHz to 20 MHz and can operate in both paired spectrum (in FDD mode) and unpaired spectrum (in TDD mode).


What does LTE-Advanced enable?

As its name suggests, this technology brings even faster data rates for 4G, with a targeted peak data rate of 1Gbps. It also helps to ease congestion in the increasingly crowded core spectrum bands, through the use of non-contiguous frequency bands.

What is it?

LTE-Advanced is standards body 3GPP’s technology candidate for the ITU-R IMT-Advanced process, which identifies ‘4G’ technologies. It incorporates higher order MIMO (4×4 and beyond) and allows multiple carriers to be bonded together into a single stream.

GSM Roaming – using your mobile device outside your network coverage area

What does GSM Roaming enable?

Customers can make and receive calls, send and receive data or access other services when travelling outside the coverage area of their home network. Subscribers only need one single number, one single bill and one single phone, in up to 219 countries.

What is it?

GSM Roaming is roaming between GSM networks – the ones most widely used across the world. It means mobile subscribers can use a visited network when travelling outside the geographical coverage area of their home network.

If the visited network is in the same country as the home network, this is known as national roaming. If the visited network is outside the home country, this is known as international roaming.

Whereas, if the visited network operates on a different technical standard than the home network, this is known as inter-standard roaming.

Roaming agreements

Roaming is technically supported by mobility management, authentication and billing procedures. Establishing roaming between network operators is based on – and the commercial terms are contained in – dedicated roaming agreements.

Find out more about how roaming works here.