Cellular glossary

AMPS (Advanced Mobile Phone System)

This is an analog system that works on an 800MHz frequency.

BlackBerry phone

The BlackBerry is a handheld wireless GSM device providing e-mail, telephone, text messaging and web browsing services.

D-AMPS (renamed TDMA Time Division Multiple Access)

This system was developed as a digital enhancement to the AMPS system via the use of dual-mode phones. In the US these phones are able to switch between the AMPS analog and TDMA digital networks, giving the user the benefit of digital in TDMA areas and the widespread coverage of analog in AMPS areas.

GPRS (General Packet Radio Service)

This technology allows faster speeds of data transmission, from your cell phone.

GSM (Global System for Mobile Communication)

GSM is the standardized system for Europe thanks to early decisions by the various governments to develop a single network. It has also been increasing in popularity around the world. GSM operates on four different frequencies.

For further information please refer to our GSM SIM card user guide.

GSM 900

This is the most widely used digital service in world.

GSM 1800

This frequency is used in Europe, Asia and Australia.
It is sometimes known as DCN (Digital Communications Network).

GSM 1900

This frequency is used in the US.
It is sometimes known as PCS (Personal Communication Services).

i-mode

i-mode is a wireless internet service which enables mobile phone users to access mobile internet sites. i-mode was launched in Japan on 22/02/99 by NTT DoCoMo.

Inmarsat

A satellite system originally developed for maritime communications but now expanded for all industries. They can provide almost total global coverage.

Iridium

A company that manufactures and runs a mobile satellite communications system. Using one of their handsets linked to their satellite network, calls can made from anywhere on the planet, no matter how remote.

MMS (Multimedia Messenger Service)

This provides delivery of personal multimedia messages from phone to phone or from phone to e-mail. In addition to the familiar text messages, multimedia messages can contain images, graphics, voice, and audio clips.

Network

The infrastructure over which mobile services can operate.

Roaming

As a result of the collaboration between different service providers, roaming is made possible. This enables phone users to call from anywhere within the participating service providers coverage area using one phone connected to one service. International roaming refers to the same agreement between the service providers of different countries allowing international calling.

SIM (Subscriber Identity Module)

The SIM card is, as the name would suggest, a proof of subscription to a specific network and, an information storage point for the details specific to the owner of the card. Thus the postage stamp sized card can be transferred between GSM phones and the user will be charged on the same tariff, have access to the same services and, retain one telephone number and the database of information they have stored.

SIM locked/unlocked

A GSM phone that is 'locked' means that it only operates with the SIM card that it is supplied with (Mobal World Phones are SIM locked to the Mobal GSM SIM card). GSM phones that are 'unlocked' work using any SIM card (if you already own an unlocked GSM phone you will be able to use the Mobal GSM SIM card). You may also see the same term described as SIM latched/unlatched.

SMS (Short Message Service)

This is a service available to most modern mobile phones providing the user the ability to send text and numeric ‘messages’, typically up to 160 characters in length, to other handsets equipped to receive them.

Voice Mail

On most modern phones voice mail is a standard service, whereby if you were unable to answer your phone then the caller would be able to leave a message.

WAP (Wireless Application Protocol)

This technology allows you to access internet pages from your cell phone.