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In mobile telephony, first-generation systems were analogue, circuit-switched. Voice links were poor, handoff unreliable, capacity low, and security non-existent. 1G systems are not now under active development – indeed, in some areas 1G spectrum is being auctioned for 2G and 3G use.


In mobile telephony, 2.5G protocols extend 2G systems to provide additional features such as packet-switched connection (GPRS) and enhanced data rates (HSCSD, EDGE).


In mobile telephony, second-generation protocols use digital encoding and include GSM, D-AMPS (TDMA) and CDMA. 2G networks are in current use around the world. These protocols support high bit rate voice and limited data communications. They offer auxiliary services such as data, fax and SMS. Most 2G protocols offer different levels of encryption.


In mobile telephony, third-generation protocols support much higher data rates, measured in Mbps, intended for applications other than voice. 3G networks trials started in Japan in 2001. 3G networks are expected to be starting in Europe and part of Asia/Pacific by 2002, and in the US later. 3G will support bandwidth-hungry applications such as full-motion video, video-conferencing and full Internet access.


Advanced Mobile Phone System: a 1G standard which operates in the 800-900MHz-frequency band. It is still widely used in the United States.


The simple way to transmit speech, which is translated into electronic signals of different frequency and/or amplitude. The first networks for mobile phones, as well as broadcast transmissions, were analogue. Due to being longer established in some countries, analogue networks may offer better coverage than digital networks, however analogue phones are less secure and suffer more from interference where the signal is weak. Analogue systems include AMPS, NMT and ETACS.


Historically, "application programming interface". Practically, an API is any interface that enables one program to use facilities provided by another, whether by calling that program, or by being called by it. At a higher level still, an API is a set of functionality delivered by a programming system, and as such the mix of APIs in a particular system tells you what that system can do.


An open specification for seamless wireless short-range communications of data and voice between both mobile and stationary devices. For instance, it specifies how mobile phones, computers and PDAs interconnect with each other, with computers, and with office or home phones. The first generation of Bluetooth permits exchange of data up to a rate of 1 Mbps per second, even in areas with much electromagnetic disturbance. It transmits and receives via a short-range radio link using a globally available frequency band (2.4 GHz ISM band).


Code Division Multiple Access: a digital wireless telephony transmission technique.
1. CDMA allows multiple frequencies to be used simultaneously (Spread Spectrum). The CDMA idea was originally developed for military use over 30 years ago.
2. The CDMA standards used for second-generation mobile telephony are the IS-95 standards championed by QUALCOMM.

Cellular radio

The technology that has made large scale mobile telephony possible. Current cellular networks reuse the same radio frequencies by assigning them to cells far enough apart to reduce interference. A cell is the geographical area covered by one radio base station transmitting/receiving in the centre. The size of each cell is determined by the terrain, transmission power, and forecasted number of users. Service coverage of a given area is based on an interlocking network of cells, called a cell system.


Means of creating a connection by setting up a dedicated end-to-end circuit, which remains open for the duration of the communication.


J2ME Connected Limited Device Configuration. The CLDC serves the market consisting of personal, mobile, connected information devices. This configuration includes some new classes designed specifically to fit the needs of small-footprint devices.


A generic name for information centric mobile phones. In effect a fully featured personal digital assistant and mobile phone in one unit. The Nokia 9210 Communicator is an example of such a Symbian OS phone.


Digital AMPS (Digital-Advanced Mobile Phone Service) is the digital wireless standard widely used throughout the Americas, Asia Pacific and other areas. D-AMPS uses digital TDMA on the one hand, and is required to be compatible with installed AMPS base station networks on the other.

DCS 1800

Digital Communications System: another name for GSM working on a radio frequency of 1800 MHz. Also known as GSM1800 or PCN, this digital network operates in Europe and Asia Pacific.


A way of encoding information. On digital networks, data doesn’t need to go though the extra step of being converted to an analogue signal, voice is sampled and coded in a way similar to how it is recorded on a CD. Digital networks are fast replacing analogue ones as they offer improved sound quality, secure transmission and can handle data directly as well as voice. Digital networks include mobile systems GSM, D-AMPS, CDMA, TDMA and UMTS.

Dual band

Dual band mobile phones can work on networks that operate on different frequency bands. This is useful if you move between areas covered by different networks. Some networks operate on two bands, for instance GSM-1800 in town centres and GSM-900 in the rest of the country.

Dual mode

Dual mode mobile phones have more than one air interface and hence can work on more than one network. One example is phones that operate on both digital and analogue networks. They are quite useful if you want the advantages of a digital phone, but regularly visit areas where analogue is the only service available.


Extended Total Access Communications System: a 1G mobile phone network developed in the UK and available in Europe and Asia.


Enhanced Data Rates for GSM Evolution. An enhanced modulation technique designed to increase network capacity and data rates in GSM networks. EDGE should provide data rates up to 384 Kbps. EDGE will let operators without a 3G license to compete with 3G networks offering similar data services. EDGE is not expected before 2001 at the earliest.


General Packet Radio Service: a radio technology for GSM networks that adds packet-switching protocols, shorter set-up time for ISP connections, and offer the possibility to charge by amount of data sent rather than connect time. GPRS promises to support flexible data transmission rates typically up to 20 or 30 Kbps (with a theoretical maximum of 171.2 Kbps), as well as continuous connection to the network. A 2.5G enhancement to GSM, GPRS is the most significant step towards 3G, needing similar business model, and service and network architectures. GPRS started to appear in some networks during 2000.


Global System for Mobile communications, the most widely used digital mobile phone system and the de facto wireless telephone standard in Europe. Originally defined as a pan-European open standard for a digital cellular telephone network to support voice, data, text messaging and cross-border roaming. GSM is now one of the world's main 2G digital wireless standards. GSM is present in more than 160 countries and according to the GSM Association, accounts for approximately 70 percent of the total digital cellular wireless market. GSM is a time division multiplex (TDM) system. Implemented on 800, 900, 1800 and 1900 MHz frequency bands.


High Speed Circuit Switched Data: dedicated circuit-switched data communications technology for GSM which boosts data throughput up to 14.4 Kbps in a single channel, and by aggregating channels, up to 57.6 Kbps. An asymmetrical service can be offered where, for instance, one channel is allocated for the uplink and several are aggregated for the downlink. HSCSD can provide a fixed bit rate (transparent mode) or a variable one (non-transparent mode). In most cases HSCSD is available to network operators as a pure software upgrade. HSCSD started to appear in some networks in 1999.


Proprietary packet-based information service for mobile phones. i-mode delivers information (such as mobile banking, and train timetable) to mobile phones and enables exchange of email from handsets on the PDC-P network. Launched in 1999 by NTT DoCoMo, i-mode is very popular in Japan (especially for email and transfer of icons), but is not currently being used elsewhere,


International Mobile Telecommunications-2000: term used by the International Telecommunications Union (ITU) for the specification for projected third-generation wireless services. Formerly referred to as FPLMTS, Future Public Land-Mobile Telephone Systems.


1. A suite of protocols for infrared (IR) exchange of data between two devices, up to 1 or 2 metres apart (20 to 30 cm for low-power devices). IrDA devices typically have throughput of up to either 115.2 Kbps or 4 Mbps. IrDA protocols are implemented in Symbian OS phones, many PDAs, printers and laptop computers.
2. The Infrared Data Association, the industry body that specifies IrDA protocols, originally founded by Hewlett-Packard and others.


Technique whereby the information (voice or data) to be sent is broken up into packets, of at most a few KB each, which are then routed by the network between different destinations based on addressing data within each packet. Use of network resources is optimized, as the resources are needed only during the handling of each packet. This is an ideal model for ad hoc data communication, and works well also for voice, video and other streamed data. Mobile phones with packet-switched communication appear to be "always connected" to the data network, whereas in the case of circuit-switched connections, setup time takes around 30 seconds to connect from a mobile phone to an ISP. Use of packet-switched network can be charged according to the volume of data transferred and not to any notion of time spent online.


A generic name for voice centric mobile phones with information capability. The Ericsson R380 Smartphone is an example of such a Symbian OS phone.


Short Message Service: available on digital GSM networks allowing text messages of up to 160 characters to be sent and received via the network operator's message centre to your mobile phone, or from the Internet, using a so-called "SMS gateway" website. If the phone is powered off or out of range, messages are stored in the network and are delivered at the next opportunity.

Symbian OS

Symbian’s advanced open standard operating system for data enabled mobile phones. It includes a multi-tasking multithreaded core, a user interface framework, data services enablers, application engines and integrated PIM functionality and wireless communications.


Universal Mobile Telecommunications Service, part of the IMT-2000 initiative, is a 3G standard supporting a theoretical data throughput of up to 2 Mbps. First trials started in 2001. It should be rolled out in most of the world by 2005.


1. Wireless Application Protocol: a set of communication protocol standards to make accessing online services from a mobile phone simple.
2. WAP was conceived by four companies: Ericsson, Motorola, Nokia, and Unwired Planet (today called The WAP Forum is an industry association with over 200 members. Symbian is a full member of the WAP Forum.


Wide-band CDMA: a CDMA protocol originated by NTT DoCoMo and now adopted for third-generation use by ETSI in Europe. WCDMA supports very high-speed multimedia services such as full-motion video, Internet access and video conferencing.

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