1G
This stands for first generation mobile phone systems. Basically, they were wireless phones bigger than bricks that only let you make voice calls. You¿re more likely to see them in museums these days as they were replaced by 2G mobiles.
2G
This stands for second generation mobile phone systems. It's the digital successor to 1G. Often also known as GSM (Global System for Mobile communication), 2G mobiles gave people the chance to send and receive text messages and small data files.
3G
This is where we come in. This stands for third generation mobile phone systems ¿ the latest step in mobile technology. 3G works at much higher speeds than 2.5G networks. It¿s what you use to surf the web on your 3 mobile, or watch TV, or play games with your mates over the other side of town, or send emails, pictures and video messages, or make video calls¿
As for the nitty-gritty, 3G provides high-speed data transmission at rates up to 384 kilobits/second or even higher with HSDPA. 3 and the other major European operators use the dominant version of 3G called UMTS which is based on Wideband-CDMA coding and compatible with the old 2.5G GSM Networks. Other technologies are also promoted as 3G, such as CDMA2000 and TD-SCDMA being developed by China. Yes. We can hear you yawning now. We¿ll stop indulging in our technology.
Access
The link between customer and telecoms network. A variety of technologies are used including copper wires, fibre optics, mobile, microwave and satellite.
Advanced Mobile Phone Service (AMPS)
Analogue cellular telephone technology used mainly in the US. Operates in the 800Mhz band frequency. This was the original American analogue cellular radio system used by AT&T (the digital enhancement was originally called D-AMPS, and is now known as TDMA). About 40% of Latin American and 25% of North American subscribers are on AMPS. The bulk of AMPS migration is to CDMA-One and TDMA.
Asymmetric Digital Subscriber Line (ADSL)
Digital technology to allow broadband service over ordinary copper telephone lines. Transmission
capacity is greater from network to customer (c1.5Mbps) than customer to network, hence asymmetric.
Attenuation
Loss of signal strength in a lightwave, electrical, or radio signal that is usually related to the distance the signal must travel. For example, fiber-optic transmission must be regenerated approximately every 30 miles. Radio signal attenuation may be due to atmospheric conditions, sun spots, antenna design or positioning, and line-of-sight obstacles. Usually expressed as a ratio in decibels (Db).
Band
The range of frequencies between two defined limits. Also refers to the term used by regulators to establish a range of charges. See Bandwidth.
Bandwidth
Range of frequencies occupied by a signal. (For example, a telephone conversation only requires 3KHz of bandwidth while hand television signals require about 3MHz of bandwidth.) The ‘necessary bandwidth’
is the amount of spectrum required to transmit the signal without distortion or loss of information. In analogue systems, it is measured in cycles per second
(Hertz) and in digital systems in binary bits per second (bps).
Base Station
Fixed radio transmitter/receiver which electronically relays signals to and from mobile terminals or handsets within a given range (a cell). Houses the equipment needed to set up and complete calls on cellular phones, ie FM radio transmitter and receiver, antenna, and computer. The base station works with the subscriber's handset and the Mobile Telephone Exchange to complete a call.
Bit
Binary Digit. Any digital transmission is composed of a series of bytes, each of which comprise eight bits. A bit is the smallest component unit of any electronic message and functions like an on/off switch using 1s and 0s. The combination of on and off in any one byte determines the content of information sent in that byte.
Bits Per Second (bps)
Rate at which individual bits are transmitted across a
communications link or circuit. One thousand bps is 1Kbps, and one million bps is 1Mbps or 1Mbit/s.
Bluetooth
Short-range wireless connection standard enabling seamless voice and data transmission via short range (up to 10 metres) radio signals. Its aim is to link a wide range of computers, electronics and telecoms devices. The technology uses a low-power, two-way radio link, which is built into a microchip. It is a global initiative by Ericsson, IBM, Intel, Nokia and Toshiba to set a standard for cable-free connectivity between mobile phones, mobile PCs, handheld computers and other peripherals.
Broadband
Transmission capacity with sufficient bandwidth to permit combined provision of voice, data and video. Unlike voice communication, requiring transmission of relatively small amounts of information, video and
multimedia services require transmission of large amounts of information.
Broadband Network
Network having a broadband capacity capable of
transmitting voice, image, video and data signals at a rate in excess of 1.5Mbps. See Narrowband Network; Wideband Network.
BWA (Broadband Wireless Access)
Service providing two-way broadband, data, voice, multimedia and information services using (mostly) millimetre wave radio links. LMDS [Local Multi-point Distribution Service) is a technology that enables BWA.
Byte
Standard unit for transmitting information from one electronic source to another. One byte comprises eight bits.
Cable TV or Community Antenna Television (CATV)
Cable TV is a service that distributes a wide range of television programmes to homes of subscribers from a central facility through co-axial cable networks. See
also Cable.
Caller Line Identification (CLI)
Service that allows customers to see the number from which someone is calling them before they answer.
Carrier (CRX)
Long-distance company which primarily uses its own
transmission facilities to carry calls, as opposed to resellers who lease or buy most or all of their transmission facilities from the carriers.
Carrier Pre-selection
Facility offered to customers which allows them to opt
for certain defined classes of call to be carried by an operator selected in advance (and having a contract with the customer), without having to dial a routing prefix or follow any other different procedure to invoke such routing.
CDMA (Code Division Multiple Access)
also known as CDMA-One, is one of the three wireless telephone transmission technologies, takes an entirely different approach from GSM and the similar TDMA. CDMA,
after digitizing data, spreads it out over the entire bandwidth it has available. Multiple calls are overlaid over each other on the channel, with each assigned a unique sequence code. CDMA claims superiority over TDMA in terms of quality, capacity and security. CDMA was commercialised by Qualcomm of the US and is most widely used in that market. The first network using this standard was built by Hutchison in Hong Kong in 1995, with US roll-outs beginning in 1996.
CDMA (Code Division Multiple Access) also known as CDMA-One
CDMA, one of the three wireless telephone transmission technologies, takes an entirely different approach from GSM and the similar TDMA. CDMA,
after digitizing data, spreads it out over the entire bandwidth it has available. Multiple calls are overlaid over each other on the channel, with each assigned a unique sequence code. CDMA claims superiority over TDMA in terms of quality, capacity and security. CDMA was commercialised by Qualcomm of the US and is most widely used in that market. See also CDMA2000, FDMA.
cdmaOne Networks using the 2G CDMA standard developed by Qualcomm and its partners. The first network using thisstandard was built by Hutchison in Hong Kong in 1995,with US roll-outs beginning in 1996. There are standards for the cdmaOne air interface: IS-95A and IS-95B, which offers higher data rates than the former.
CDMA2000
3G technology developed by Qualcomm of the US. Thisis in competition with W-CDMA, developed by the GSM community as the worldwide standard for 3G mobile. An evolutionary upgrade from cdmaOne.
CDMA2000 1x
First step in the evolution to 3G, which improves packet
data transmission capabilities and speeds in the network, and also boosts voice capacity by nearly two times over today’s CDMA capacities. CDMA2000 1xEV represents the second step in the evolution of CDMA2000 and will bring data rates of up to 2Mbits/s to the network.
CDMA2000 1xEV
EV stands for evolution. 1xEV can be deployed either
on its own as a mobile data network, or in conjunction with CDMA2000 1x. 1xEV will arrive in two stages, the first offering support for data only, the second combining data and voice.
CDPD (Cellular Digital Packet Data)
Data transmission technology developed for use on cellular phone frequencies. CDPD uses unused cellular
channels (in the 800– 00MHz range) to transmit data in packets. This technology offers data transfer rates of up to 19.2Kbps, quicker call set up and better error correction than using modems on an analogue cellular
channel. Transmits packets of data over cellular networks without interfering with voice transmission.
Cell
Geographic area in cellular telephone systems in which all cellular transmissions are controlled by a single cell site.
Cell Switching
Feature that enables a caller to move from one location
to another without losing the connection. The cellular system is designed to switch calls to a new call without a noticeable drop in the connection. While not noticeable in voice communications, the 300 milliseconds required for cell switching can cause problems in data transmission.
Channel
Telecommunications path of a specific capacity and/or speed between two or more locations on a network. The channel may be established via wire, radio (microwave), fibre or a combination of the three.
Circuit Switching
Traditional network design in which the switch keeps a
path open between the caller and called party for the duration of the call. Most voice calls are circuit switched to maintain real-time transmission while many data calls are packet switched for greater efficiency at the expense of some transmission delays.
Convergence
The coming together of a number of different technologies and information including the Internet and devices such as television, mobile phones and PCs. See also Fixed to Mobile Integration (FMI).
D-AMPS (Digital Advanced Mobile Phone Service)
Cellular phone service, using the TDMA technology. Analogue systems can be upgraded to D-AMPS.
Deregulation
Removing regulatory barriers governing service or provider, thereby encouraging free competition.
DG XIII
European Commission’s directorate general for telecommunications, information industries and innovation.
Digital European Cordless Telecommunications (DECT)
A wireless, short-term transmission standard used in Europe, often for cordless telephones and, potentially, for Net devices like smart home gateways
Digital Subscriber Line (DSL)
Technology for bringing high-bandwidth information to homes and small businesses over ordinary copper telephone lines. xDSL refers to different variations of DSL, such as ADSL, HDSL, SDSL and VDSL.
Dual Tone Multi Frequency (DTMF)
Type of signalling which emits two distinct frequencies within the voice band for each indicated/pressed digit.
ECSD (Enhanced Circuit Switched Data)
ECSD is likely to be the less popular of the two EDGE options available, focused mainly on applications that require a continuous stream of data.
EDGE (Enhanced Data GSM Environment)
EDGE is one of the three technology upgrade options available to GSM networks, along with GPRS and
HSCSD. EDGE is designed to deliver data at rates up to 384Kbps and enable the delivery of multimedia and other broadband applications to mobile phone and computer users. The EDGE standard is built on the existing GSM standard, using the same TDMA frame structure and existing cell arrangements. There will be two versions of EDGE, ECSD and EGPRS.
EFR (Enhanced Full Rate) Technology which improves the quality of calls made on a digital mobile network, to the extent that they are of equivalent quality to those made on a fixed line call. It is achieved through more efficient use of bandwidth.
EFR (Enhanced Full Rate)
Technology which improves the quality of calls made on a digital mobile network, to the extent that they are of equivalent quality to those made on a fixed line call. It is achieved through more efficient use of bandwidth.
EGPRS (Enhanced General Packet Radio Systems)
EGPRS enhances the speeds of GPRS and is targeted at improving internet download times.
EMI (Electromagnetic Interference)
Undesirable response in the operation of electronic systems or equipment due to electromagnetic energy.
Erlang
Unit of traffic volume corresponding to the number of simultaneous calls in progress at any given time or averaged over a period of time.
FDMA (Frequency division multiple access)
Division of the frequency band allocated for wireless cellular telephone communication into 30 channels,
each of which can carry a voice conversation or, with digital service, carry digital data. FDMA is a basic technology used in the analogue AMPS the most widely-installed cellular phone system installed in North America. With FDMA, each channel can be assigned to only one user at a time. The D-AMPS also uses FDMA but adds TDMA to get three channels for each FDMA channel, tripling the number of calls that can be handled on a channel. It can also be used in fixed networks.
Fibre Channel
High speed fibre-optic network system intended to
support transmission speeds of up to 10Gbits/s plus.
Fibre Optics
Flexible glass or plastic rods that use light to transmit
audio, video and data signals. Particularly suitable for digital communications as information is transferred by modulating the transmitted light. Has both a much higher transmission speed and capacity than copper wire or cable and is not subject to interference or noise. Fibre optics permit fast and high quality two-way, full-motion video and two-way audio interaction between participating sites, in addition to simple data transmissions. Bandwidth capacity of fibre-optic cable is much greater than that of copper wire.
Fixed-Line Network
Basic telephone network comprising subscriber lines, exchanges and inter-exchange lines. See PSTN.
Fixed to Mobile Integration (FMI)
Merging of fixed and mobile services into an integrated service whereby the customer will be offered both fixed and mobile services and will receive one bill and/or receive and make calls using one handset. Also know as fixed to mobile convergence (FMC).
Freedom of Mobile Multimedia Access (FOMA)
NTT DoCoMo’s brand name for 3G services, based on the W-CDMA format.
Frequency
Number of complete cycles per unit of time, denoted by Hertz (Hz). 1 Hz = 1 cycle per second.
Frequency Band Allocation
Frequency band that is allocated to a service provider on which it is licensed to conduct business.
Frequency Modulation (FM)
Use of various frequencies to convey an analogue or digital signal. With frequency modulation, the frequency of the carrier is varied according to the amplitude of the transmitted signal. FM radio is an example of frequency modulation. AM varies the amplitude of the signal while FM varies the frequency. See also VHF.
Frequency Spectrum
Spectrum available for communication. Regulatory agencies monitor the occupancy of the radio spectrum and allocate to individual/group users to enable a large number of services to operate within specific limits of interference.
Generation
As in ‘third generation’. Refers to the type of technology used in a particular mobile phone network. Analogue was first generation, digital was second and UMTS is the third.
Global System for Mobile (GSM)
GSM is the de facto wireless telephone standard in Europe. GSM is based on TDMA and is the most widely used of the three digital wireless telephone technologies (TDMA, GSM, and CDMA). Digital systems offer higher transmission rates, low noise, improved security, international roaming capabilities and better spectrum utilisation relative to an analogue system. Also known as 2G. See also FDMA.
GPRS (General Packet Radio Services)
GPRS is one of three technology upgrade options for GSM networks, along with HSCSD and EDGE. It is a packet-based wireless communication service which when available (late 2000 early 2001) promises data rates from 8.8 up to 114 Kbps and continuous connection to the internet for mobile phone and computer users. GPRS is based on GSM communication and will complement existing services such as circuit-switched cellular phone connections and SMS.
HSCSD (High Speed Circuit Switched Data)
HSCSD (High Speed Circuit Switched Data) One of three technology developments along with EDGE and GPRS which provides an upgrade of the
GSM networks to improve their data capability. HSCSD increases speed sufficiently for the very basic video transmission and internet access at rates close to existing fixed line rates. HSCSD did not become commercially available until 2000.
i-Mode
i-Mode is the packet-based service for mobile phones offered by Japan’s leader in wireless technology, NTT DoCoMo. Unlike most of the key players in the wireless arena, i-Mode ignored WAP and uses a simplified version of HTML, Compact Wireless Markup Language (CWML) instead of WAP’s WML. NTT DoCoMo has said that eventually it will support WAP and WML, but the company has not said exactly when this will happen. First introduced in 1999, I-Mode was the worlds first smart phone for Web browsing.
Integrated Services Digital Network (ISDN)
International standard which enables high speed simultaneous transmission of voice and/or data over an existing PSTN. Provides end-to-end digital connection for multiplexed communication channels. The most common ISDN system provides one data and two voice channels over a traditional copper wire pair, but can represent as many as 30 channels.
Internet
The global network of networks. It uses IP to link the various physical networks into a single network.
Intranet
Closed data network (non-public) linking a number of sites. Could be regarded as an ‘internal internet’.
ISP (Internet Service Provider)
Company that provides individuals and other companies access to the internet
Liberalisation
Opening up a country’s telecoms market to competition. Pan-European telecom liberalization occurred for most European countries on 1 January 1998.
Licensing
Administrative procedure for selecting operators and awarding franchises for the operation of particular telecoms services, eg mobile licences
Microwave
High capacity radio waves used for point-to-point and
multi-directional communication of audio, data and
video signals. Microwave frequencies require direct line
of sight between sending and receiving station to
operate.
MIN (Mobile identification number)
Uniquely identifies a mobile unit in a wireless carrier’s network, and can be used to dial from another network
or fixed line and can be electronically checked to help prevent fraud.
Mobile Communications
Wireless form of communication through which signals are transmitted and received via microwaves. This type of communication allows customers to talk on a line and/or send and receive data signals while moving around from place to place. The signals are
automatically bounced between base stations to the closest one as the customer moves around.
Modem
Device which enables data to be exchanged by interpreting and converting signals. A modem can convert a digital signal to an analogue signal, allowing computers to transmit and receive data, such as analogue Voice signals, over conventional telephone lines. Modems work in pairs, so at the other end of the channel the signal is returned to digital form. See
Multimedia Messaging Service (MMS)
Electronic message service where the messages can comprise a combination of text, sounds, images and video. Only available on MMS capable handsets.
Multiplexing
Act of combining a number of individual message
circuits for transmission over a set level of bandwidth.
MVNO (Mobile Virtual Network Operator)
Mobile resellers that do not own networks but rather purchase wholesale minutes from one of the national
incumbent mobile operators.
Network Architecture
Set of design principles defining the protocol, functions and logical components of a network and how they should perform.
Packet
Unit of data that is routed between an origin and a destination on the internet or any other packet-switched network. Each packet is separately
numbered and includes the internet address of the destination. The individual packets for a given file may travel different routes through the internet. When they have all arrived, they are reassembled into the original file.
Packet Switching
Process of transmitting digital information by means of
addressed packets so that a channel is occupied only during transmission of the packet. In contrast, data sent using circuit switching net modems occupies a circuit for the entire duration of transmission, even when no data is actually travelling over lines. Using packet switching, various packets of information can travel along different routes on the network, allowing the carrier to optimise network capacity.
Personal Communications Network/System (PCN/PCS)
Generic term used to describe the digital cellularservice that is based on existing GSM and ISDN
Standards. It is intended to be a mass-market service to rival PSTN. PCN/PCS operates at 1800MHz (and above) that is higher than analogue frequencies, so achieving greater capacity potential.
Point of Presence (PoP)
City or other location where the phone company
network can connect to other networks or services. PoPs increase as a company rolls out its network increasing service availability.
Protocol
Format or set of rules and conventions that control the format and relative timing of message transmission between two points on a telecom connection or a computer network.
Public Switched Telephone Network (PSTN)
Infrastructure providing a country’s telephone system. It is the means by which household and business
phones are connected, typically by conventional fixed cables.
Pulse
Variation in electrical energy above or below a normal level and a given duration, such as a brief surge of voltage or current.
Real Time
Transmission or data processing operational mode in which the data is entered in an interactive (two way communication) session. Such applications are fast enough to affect later data input. Used in the streaming
of video and audio applications.
Remote Access
Sending and receiving data to and from a computer
through communications links such as phone lines.
Roaming
Describes mobile cellular telephone use which involves
passing from the local service area of one company to that of another with a compatible network technology. This can also be done at the international level. Within your home network, this means that your mobile phone
automatically sets up communication procedures with different radio base stations when on the move.
Signalling
Act of sending messages between network switches and/or control points that convey information about circuit status, traffic loads, call routing and other immediate aspects of network operations.
SIM (Subscriber Identity Module) Card
Chip which authenticates the user’s GSM mobile phone and allows calls to be made. Stores the user’s personal
profile and other information. Without the SIM card, calls cannot be made.
Smart Antenna
Antenna system whose technology enables it to focus its beam on a desired signal to reduce interference.
SMS (Short Messaging Service)
Electronic messages on a digital wireless network, allowing messages of up to 160 characters to be sent and received via the network operator¿s message centre.
Spectral Management
Management of the type and quantity of devices
connected to the copper pairs to eliminate any interference between services on cable, and between those external radio services.
Spectrum Auction
When extra spectrum capacity becomes available it is
usually sold via an auction process.
Telecoms
The transmission and reception of voice, data or other signals through electrical impulses. Includes all aspects of transmitting information.
Time Division Multiple Access (TDMA)
2G technology developed in the US. Divides each cellular channel into three (GSM has eight) time slots in order to increase the amount of data that can be carried. Each user making a call is allocated a particular time slot, which he occupies for the duration of the call. TDMA-based cellular systems include European GSM, Japanese PDC and North American D-AMPS. However, each of these systems implements TDMA in a different and incompatible way. (See also CDMA and FDMA.)
Tri-band
Term applying to cellular handset/phone that will work on 800MHz analogue, 800MHz digital and 1900MHz frequencies. A tri-band cellular phone will operate on three different frequencies, depending on the available network. Outside America, the GSM frequencies used are 900MHz and 1800MHz. ’American GSM’, or PCS, operates at 1900MHz. The introduction of tri-band phones is a further step towards true worldwide roaming.
Universal Mobile Telecommunications System (UMTS)
A so-called ‘third-generation (3G)’ broadband, packet-based transmission of text, digitised voice, video, and multimedia at data rates up to and possibly higher than 2Mbps. See also GSM, GPRS, CDMA, TDMA.
Unpaired Spectrum
Used for one-way traffic to reflect the asymmetrical
nature of some multimedia services. For example, an e-mail with a video clip is an asymmetric multimedia application—you only download data. This is different from Paired Spectrum which is used for the purpose of two-way communication, ie video-conferencing is symmetric—there is a continuous stream of information to and from the handset.
Value Added Network (VAN)
Communications network that provides features such as message switching and protocol handling.
Value Added Services (VAS)
Services other than the standard voice
communication facility offered by the telco. These include voicemail, caller line identification and call waiting. Requires a digital network. VDSL (Very high
data rate Digital Subscriber Line) Developing technology that promises much higher data rates over relatively short distances (between 51 and 55 Mbps over lines up to 1,000 feet or 300 meters in length). It is envisioned that VDSL may emerge after ADSL is widely deployed and co-exist with it. A
number of standards organisations are working on it.
Voice Frequency (VF)
Any of the frequencies in the band 300–3,400Hz which must be transmitted to reproduce the voice with a reasonable degree of clarity.
Voice Grade (VG)
Access line suitable for voice. Generally, it has a
narrowband frequency range of about 300¿3000Hz. A low-capacity communications circuit/path. It usually implies a speed of 56Kbps or less. (Contrast with wideband and broadband.)
Wave Division Multiplexing (WDM)
Technology increasing fibre optic cable capacity by using several different light waves on a single fibre. See multiplexing.
W-CDMA (Wideband code division multiple access)
Third generation standard developed and supported by GSM proponents. The natural upgrade from GSM and Japanese PDC. See also CDMA, FDMA, TDMA, UMTS.
Wideband
Term applied to facilities or circuits where bandwidths are greater than required for a single voice channel. Usually implies a speed from 64Kbps
to 1.544Mbps.
Wideband Network
Capacity of a wideband network lies between that of a
broadband network and that of a narrowband network. Services may include video teleconferencing, file transferring and video telephony.
WIN (Wireless intelligent network)
Architecture of the wireless switched network that allows carriers to provide enhanced and customised services for mobile telephones.
Wireless Communications
System that uses radio transmitters and receivers in place of wire lines which, when connected to the
evolving public switched network (PSN), provides comprehensive telephone service to customers.
Wireless Local Loop (WLL)
Wireless connection of a telephone in a home or
office to a fixed telephone network.