Wireless: Glossary of Terms
This Glossary of Terms has been provided by CTIA, the Cellular Telecommunications & Internet Association. CTIA is the voice of the wireless industry - representing its members in a constant dialogue with policy makers in the Executive Branch, in the Federal Communications Commission, and in Congress, CTIA's industry committees provide leadership in the area of taxation, roaming, safety, regulations, fraud and technology. For more information on the wireless industry, please visit www.wow-com.com or to learn more CTIA's two annual tradeshows, please visit www.wirelessIT.com or www.ctiashow.com.
3G Third Generation Wireless
The next step in the development of wireless communications. The first generation was analog and the second was digital (CDMA, TDMA and GSM). Third generations systems are expected to provide broadband, high-speed data applications - both fixed and mobile.
Acknowledgment
The transmission of a short packet from the receiving device to the sending device to indicate that the data sent has been received error-free.
AIN (Advanced Intelligent Networks)
Refers to networks that route calls based on database information that can affect the inbound and outbound flow of the call.
Air Time
Actual time spent talking on the wireless telephone. Most carriers bill customers based on how many minutes of air time they use each month. The more minutes of time spent talking on the phone, the higher the bill.
Alphanumeric
A message or other type of readout containing both letters ("alphas") and numbers ("numerics"). Regarding wireless, "alphanumeric memory dial" is a special type of dial-from-memory option that displays both the name of the individual and that individual's phone number on the wireless phone handset. The name also can be recalled by using the letters on the phone keypad. By contrast, standard memory dial recalls numbers from number-only locations.
AMPS (Advanced Mobile Phone Service)
The term used by AT&T's Bell Laboratories (prior to the break-up of the Bell System in 1984) to refer to its cellular technology. The AMPS standard has been the foundation for the industry in the United States, although it has been slightly modified in recent years. "AMPS-compatible" means equipment designed to work with most cellular telephones.
Analog
The traditional method of modulating radio signals so that they can carry information. AM (amplitude modulation) and FM (frequency modulation) are the two most common methods of analog modulation. Though most U.S. cellular systems today carry phone conversations using analog, some have begun offering digital transmission. See also Digital Modulation.
ANSI (The American National Standards Institute)
A non-profit, privately funded membership organization that coordinates the development of U.S. voluntary national standards and is the U.S. representative to non-treaty international standards-setting entities including the International Organization for Standardization (ISO) and the International Electrotechnical Commission.
Antenna
A device for transmitting and/or receiving signals. The size and shape of antennas are determined, in large part, by the frequency of the signal they are receiving. Antennas are needed on both the wireless handset and the base station.
API
Application Programming Interface software used by an application program to request and carry out lower-level services performed by a computer's or telephone system's operating system.
ARDIS (Advanced Radio Data Information System)
A nationwide, public two-way wireless packet data network, originally developed by IBM, now owned and operated by Motient.
ASCII (American Standard Code for Information Interchange)
A standard code used by computer and data communication systems for translating characters, numbers, and punctuation into digital form. ASCII characters can be recognized by computer and communications devices using a variety of applications.
ATM (Asynchronous Transfer Mode)
A very high-speed transmission technology. ATM is a high bandwidth, low-delay, connection-oriented switching and multiplexing technique. There are efforts underway to develop wireless ATM networks.
Authentication
A process used by the wireless carriers to verify the identity of a mobile station.
AVL (Automatic Vehicle Location)
The ability to pinpoint the location of a vehicle within a given range.
Bandwidth
A relative range of frequencies that can carry a signal without distortion on a transmission medium.
Base Station
The central radio transmitter/receiver that maintains communications with mobile radiotelephones within a given range (typically a cell site). See also Cell, Cell Site.
Bluetooth
A technology specification for small form factor, low-cost, short range radio links between mobile PCs, mobile phones, and other portable devices. It is expected to enable users to connect a wide range of computing and telecommunications devices without the need to connect cables.
BPS (Bits Per Second)
The unit of measurement for the rate at which data is transmitted.
Browser
Software which moves documents on the World Wide Web to your computer, PDA, or phone. See HDML, HTML, HTTP and WML.
BTA (Basic Trading Area)
A service area designed by Rand McNally and adopted by the FCC to promote the rapid deployment and ubiquitous coverage of Personal Communications Services (PCS). Built from county boundaries, BTAs generally cover a city and its surrounding environs. BTAs are component parts of Major Trading Areas (MTAs). There are 493 BTAs in the United States. See also MTA.
CAI (Common Air Interface)
A standard for the interface between a radio network and equipment. A CAI allows multiple vendors to develop equipment which will interoperate.
CDMA (Code Division Multiple Access)
A spread-spectrum approach to digital transmission. With CDMA, each conversation is digitized and then tagged with a code. The mobile phone is then instructed to decipher only a particular code to pluck the right conversation off the air. The process can be compared in some ways to an English-speaking person picking out in a crowded room of French speakers the only other person who is speaking English. See also Digital Modulation.
CDPD (Cellular Digital Packet Data)
Technology that allows data files to be broken into a number of "packets" and sent along idle channels of existing cellular voice networks.
Cell
The basic geographic unit of a wireless system. Also, the basis for the generic industry term "cellular." A city or county is divided into smaller "cells," each of which is equipped with a low-powered radio transmitter/receiver. The cells can vary in size depending upon terrain, capacity demands, etc. By controlling the transmission power, the radio frequencies assigned to one cell can be limited to the boundaries of that cell. When a wireless phone moves from one cell toward another, a computer at the Mobile Telephone Switching Office (MTSO) monitors the movement and at the proper time, transfers (or "hands off") the phone call to the new cell and another radio frequency. The hand-off is performed so quickly that it's unnoticeable to the callers. See also Base Station, Cell Site.
Cell Site
The location at which communications equipment is located for each cell. A cell site includes antennas, a support structure for those antennas, and communications equipment to connect the site to the rest of the wireless system. This equipment is normally housed in a small shelter at the base of the site. Although many antennas are placed on towers, where existing structures provide for a site that is higher than its surroundings, antennas will be placed on them. For example, antennas have been placed on water towers, grain silos, and building rooftops. See also Base Station, Cell.
Channel
A path along which a communications signal is transmitted.
Circuit Switched
A switching technique that establishes a dedicated and uninterrupted connection between the sender and the receiver.
Client-Server
A computer network system in which programs and information reside on the server and clients connect to the server for network access.
CMRS (Commercial Mobile Radio Service)
The regulatory classification that the FCC uses to govern all commercial wireless service providers, including Personal Communications Services, cellular, and Enhanced Specialized Mobile Radio.
Co-Location
The siting of two or more separate companies' wireless antennas on the same support structure. See also Cell Site.
Compression
Reducing the size of data to be stored or transmitted in order to save transmission time, capacity, or storage space.
CUG (Closed User Group)
Selected user groups that communicate freely within the group, but have restricted incoming, and often outgoing, communications.
D-AMPS (Digital Advanced Mobile Phone Service)
A North American term for digital cellular radio.
DBS (Direct Broadcast Satellite)
A high-powered satellite, or satellite service, which sends signals to relatively small dishes installed at homes and office buildings.
DECT (Digital European Cordless Telephone)
A cordless telephone standard, based on Time Division Multiple Access, developed in Europe for applications in wireless PBXs, residential, and public limited-range wireless services.
DES (Data Encryption Standard)
A 56-bit, private key, symmetric cryptographic algorithm for the protection of unclassified computer data developed by IBM in 1977.
Dial-Up
The use of a standard telephone to create a telephone or data call.
Digital Modulation
A method of encoding information for transmission. Information (in most cases a voice conversation) is turned into a series of digital bits - the 0s and 1s of computer binary language. At the receiving end, the information is reconverted to its original form. Digital transmission offers a cleaner signal and is less immune to the problems of analog modulation such as fading and static. (To appreciate the difference, compare the fidelity of a standard LP record with that of a digital compact disk). Digital transmission has been embraced by the wireless industry because it offers major gains in capacity compared to analog. See also CDMA, TDMA, and GSM.
DSP (Digital Signal Processor)
A specialized computer chip that performs calculations on digitized signals that were originally analog and then sends the results.
E-mail (Electronic Mail)
Messages sent across communications networks-both wireless and landline.
EMC (Electromagnetic Compatibility)
The ability of equipment or systems to be used in their intended environment within designed efficiency levels without causing or receiving degradation due to unintentional electromagnetic interference. Proper shielding of devices reduces interference.
ESMR (Enhanced Specialized Mobile Radio)
Digital mobile telephone services offered to the public over channels previously used for two-way analog dispatch services. See also SMR.
Encryption
The transformation of data, for the purpose of privacy, into an unreadable format until reformatted with a decryption key. "Public key" encryption utilizes the RSA (which stands for its developers, Rivest, Shamir, and Adleman) encryption key. PGP, or Pretty Good Privacy, is a cryptography program for computer data, e-mail, and voice conversation.
ESN (Electronic Serial Number)
The unique number assigned to a wireless phone by the manufacturer. According to the Federal Communications Commission, the ESN is to be fixed and unchangeable - a sort of unique fingerprint for each phone. See also MIN.
ETACS (Extended Total Access Communications Systems)
The conventional wireless technology used in the United Kingdom and other countries. It was developed from the U.S. AMPS technology.
Extranet
An Intranet-like network which a company extends to conduct business with its customers and/or its suppliers. Extranets generally have secure areas to provide information to customers and external partners.
FCC (Federal Communications Commission)
The government agency responsible for regulating telecommunications in the United States.
FDMA (Frequency Division Multiple Access)
Method of radio transmission that allows multiple users to access a group of radio frequency bands without interference.
FHSS (Frequency Hopping Spread Spectrum)
A technique used in spread spectrum radio transmission systems, such as wireless LANs and some PCS cellular systems, that involves the conversion of a data stream into a stream of packets.
Frequency
A measure of the energy, as one or more waves per second, in an electrical or light-wave information signal. A signal's frequency is stated in either cycles-per-second or Hertz (Hz). See also Hertz.
Frequency Re-Use
The ability to use the same frequencies repeatedly within a single system, made possible by the basic design approach for wireless. Since each cell is designed to use radio frequencies only within its boundaries, the same frequencies can be re-used in other cells not far away with little potential for interference. The concept is akin to an FM radio station in Chicago using the same frequency as one in Denver without interference. The re-use of frequencies is what allows a wireless system to handle a huge number of calls with a limited number of channels.
GHz (GigaHertz Billions of Hertz)
Personal Communications Services operate in the 1.9 GHz band of the electromagnetic spectrum. See also Hertz, KHz, MHz.
GPRS (General Packet Radio Service)
An extension to the GSM standard to include packet data services. It is expected to be launched in 2000.
GPS (Global Positioning System)
A satellite system using 24 satellites orbiting the earth at 10,900 miles that enables users to pinpoint precise locations using the satellites as reference points.
GSM (Global System for Mobile Communications)
A world standard for digital wireless transmissions. GSM is the most widely used standard in the world today with more than 150 million users worldwide. See also TDMA.
GSO (Geosynchronous Satellite Orbit)
A satellite in orbit 23,000 miles over the equator with an orbit time of 24 hours. Also known as geostationary.
Guyed
A type of wireless transmission tower that is supported by thin guy wires. See also Monopole.
GUI (Graphical User Interface)
A name for any computer interface that substitutes graphics for characters.
Hand-Off
The process by which the Mobile Telephone Switching Office (MTSO) passes a wireless phone conversation from one radio frequency in one cell to another radio frequency in another cell. It is performed quickly enough that callers don't notice. See also MAHO.
Hands-Free
A feature that permits a driver to use a wireless car phone without lifting or holding the handset. An important safety feature.
HDML (Handheld Device Markup Language)
A modification of standard HTML, developed by Phone.com for use on small screens of mobile phones, PDAs, and pagers. HDML is a text-based markup language which uses HyperText Transfer Protocol (HTTP) and is compatible with Web servers.
Hertz
A measurement of electromagnetic energy, equivalent to one "wave" or cycle per second. See also KHz, MHz, GHz.
HTML (HyperText Markup Language)
An authoring software language used on the Web. HTML is used to create Web pages and hyperlinks.
HTTP (HyperText Transfer Protocol)
The protocol used by the Web server and the client browser to communicate and move documents around the Internet.
iDEN (Integrated Dispatch Enhanced Network)
A wireless technology developed by Motorola that works in the 800 MHz, 900 MHz, and 1.5 GHz radio bands. The technology supports, on one handset, voice-both dispatch radio and using PSTN connection-numeric paging, Short Message Service (SMS), data and fax transmission.
IMSI (International Mobile Station Identifier)
A number assigned to a mobile station by the wireless carrier uniquely identifying the mobile station nationally and internationally. See also MIN, TMSI
IMT-2000 (International Mobile Telecommunications-2000)
The standard for third-generation mobile communications systems. In Europe, it is called UMTS and in Japan it is called J-FPLMTS.
Infrared
A band of the electromagnetic spectrum used for airwave communications and some fiber-optic transmission systems. Infrared is commonly used for short-range (up to 20 feet) through-the-air data transmission. Many PC devices have infrared ports, called Infrared Serial Data Link (IRDA), to synchronize with other devices. IRDA supports speeds up to 1.5 Mbps.
Interconnection
The routing of telecommunications traffic between the networks of different communications companies.
Internet
A global network of linked computer networks made user-friendly, thus popularized, by a graphical interface called the World Wide Web.
Intranet
An internal network, which is private or employs a firewall to secure it from outside access, that supports Internet technology. The intranet is used for inter-company communications and can be accessed only by authorized users.
IP (Internet Protocol)
See TCP/IP.
ISM Band (Industrial Scientific Medical Band)
Frequency bands in the radio spectrum that are unlicensed, meaning they can be used for a variety of applications without the requirement for FCC permission. The bands are used traditionally for in-building and system applications such as bar code scanners and wireless LANs. Because there is no licensing requirement, there exists the potential for interference. Therefore, spread spectrum technology is often used to protect the integrity of data transmission.
IXC (Interexchange Carrier)
A long-distance phone company.
Java
A programming language from Sun Microsystems which abstracts data on bytecodes so that the same code runs on any operating system. Java software is generally posted on the Web and downloadable over the Internet to a PC. HotJava is installed on a Web browser and enables Java programs to be delivered over the Web and run on a PC.
Jini
A technology from Sun Microsystems that is expected to enable devices to link together to form an ad hoc community, without installation or human intervention.
J-FPLMTS (Japanese Future Public Land Mobile Telecommunications Services)
The Japanese equivalent of the IMT-2000 third-generation technology standard.
KHz (KiloHertz Thousands of Hertz)
Each wireless phone call occupies only a few KiloHertz. See also Hertz, MHz, GHz.
LAN (Local Area Network)
A data communications network, typically within a building or campus, to link computers and peripheral devices under some form of standard control.
LEC (Local Exchange Company)
The traditional, local, wired monopoly phone company.
LEO (Low Earth Orbit)
An orbital plane a few hundred miles above the earth. A new generation of communications satellites are being launched in this orbit. LEO satellites are generally divided into two groups big and little LEOs, with each group assigned specific radio frequencies. Big LEOs support both voice and data communications while little LEOs support only data communications.
LMDS (Local Multipoint Distribution System)
A system developed by Bellcore for Wireless Local Loop (WLL) applications. In the U.S., the FCC set aside a total LMDS bandwidth of 1.15 GHz in the 28-GHz, 30-GHz and 31-GHz frequency bands. LMDS supports voice and high-speed interactive data, with the potential to provide bandwidth of as much as 500 Mbps.
MAN (Metropolitan Area Network)
A network covering a larger area than a Local Area Network (LAN) and less than a Wide Area Network (WAN). Typically, a MAN connects two or more LANs. In addition to data, a MAN may also carry voice, video, image and multimedia.
Message Alert
A light or other indicator on a wireless phone that notifies a user that a call has come in. A useful feature especially if the wireless subscriber has voice mail. Also called a "call-in-absence" indicator.
MHz (MegaHertz)
Millions of Hertz Cellular and ESMR systems operate in the 800 and 900 MHz bands of the electromagnetic spectrum. See also Hertz, KHz, GHz.
MIN (Mobile Identification Number)
A number assigned by the wireless carrier to a customer's phone. The MIN is meant to be changeable, since the phone could change hands or a customer could move to another city. See also ESN, IMSI, TMSI.
MIME (Multipurpose Internet Mail Extensions)
The standard format, developed and adopted by the Internet Engineering Task Force (IETF), for including non-text information in Internet mail, thus supporting the transmission of mixed-media messages across TCP/IP networks. In addition to covering binary, audio, and video data, MIME is the standard for transmitting foreign language text which cannot be represented in ASCII code.
MMDS (Microwave Multi-point Distribution System or Multipoint Multichannel Distribution Service)
A method of distributing cable television signals through microwave from a single transmission point to multiple receiving points.
MSS (Mobile Satellite Service)
Communications transmission service provided by satellites. A single satellite can provide coverage to the entire United States.
Mobitex
A cellular land radio-based packet switched data communications system used by BellSouth's two-way packet data network and developed by Ericsson.
Modem (MOdulator/DEModulator)
A hardware device which converts digital data into analog and vice versa to enable digital signals from computers to be transmitted over analog telephone lines.
Monopole
A slender self-supporting tower on which wireless antennas can be placed. See also Guyed.
MSA (Metropolitan Statistical Area)
An MSA denotes one of the 306 largest urban population markets as designated by the U.S. government. Two cellular operators are licensed in each MSA. See also CGSA, RSA.
MTA (Major Trading Area)
A service area designed by Rand McNally and adopted by the FCC to promote the rapid deployment and ubiquitous coverage of Personal Communications Services (PCS). Built from Basic Trading Areas (BTAs), MTAs are centered on a major city and generally cover an area the size of a state. There are 51 MTAs in the United States. See also BTA.
MTSO (Mobile Telephone Switching Office)
The central computer that connects a wireless phone call to the public telephone network. The MTSO controls the entire system's operations, including call monitoring, billing, and hand-offs.
NAM (Number Assignment Module)
The NAM is the electronic memory in the wireless phone that stores the telephone number and electronic serial number.
Network Computer
An inexpensive (approximately $500) personal computer that does not have a hard disk, but can be used to browse the Internet and run applications on a server on the Internet or corporate intranet. The concept of the network computer, an inexpensive easy-to-use tool for the masses, is promoted by Oracle.
Nondirectional Antenna
An antenna that transmits and receives equally well in all directions, usually on one plane; also called an omnidirectional antenna.
Nonionizing Emissions
Radio waves, infrared rays, and visible light rays, none of which can affect an atom's electrical balance.
Non-Wireline Cellular Company
The Block "A" carrier. The "A" originally stood for "alternate," i.e., the non-Bell or "B" carrier in a market. The FCC, in setting up the licensing and regulatory rules for cellular, decided to license two cellular systems in each market. It reserved one for the local telephone company and opened a second system - the Block A system - to other interested applicants. The distinction between Block A and Block B was meaningful only during the licensing phase at the FCC. Once a system is constructed, it can be sold to anyone. Thus in some markets today, both the A and B systems are owned by telephone companies - one happens to be the local phone company for the area and the other is a phone company that decided to buy a cellular system outside its home territory. See also Wireline Cellular Company.
Operating System
A software program which manages the basic operations of a computer system. These operations include memory apportionment, the order and method of handling tasks, flow of information into and out of the main processor and to peripherals, etc. Companies involved in wireless data operating systems include Microsoft and Symbian.
Packet
A bundle of data organized in a specific way for transmission. The three principal elements of a packet include the header, the text, and the trailer (error detection and correction bits).
Packet Radio
The transmission of data over radio using a version of the X.25 data communications protocol. The data is broken into packets and transmitted wirelessly.
Packet Switching
Sending data in packets through a network to a remote location. The data sent is assembled by the PAD (see definition), often called a "modem," into individual packets of data.
PAD (Packet Assembler/ Disassembler)
A device that assembles characters into packets that are transmitted by a packet switching network. A PAD also receives packets and disassembles them into a format that can be handled by the terminal or host.
Pager
Small portable receivers that are generally inexpensive, reliable, and have nationwide coverage. Pagers began as one-way devices, but two-way paging capabilities are available over some networks, notably packet data and narrowband PCS networks.
PC Card
The new name for PCMCIA cards (see definition). A small, credit-card sized device, compatible with the PCMCIA PC Card Standard, that packages for memory and input/output.
PCMCIA (Personal Computer Memory Card International Association)
A standards body that sets the standards for PC cards.
PCS (Personal Communications Services)
FCC terminology describing two-way, personal, digital wireless communications systems. Several traditional cellular companies now offer PCS services.
PDA (Personal Digital Assistant)
Portable computing devices capable of transmitting data. These devices make possible services such as paging, data messaging, electronic mail, stock quotations, handwriting recognition, personal computing, facsimile, date book, and other information-handling capabilities.
Picocell
A wireless base station with extremely low output power designed to cover an extremely small area, such as one floor of an office building.
PIM (Personal Information Manager)
Also known as a "contact manager," is a form of software that logs personal and business information, such as contacts, appointments, lists, notes, occasions, etc.
POS (Point-of-Sale Terminal)
A type of computer terminal used to collect and store retail sales data. Wireless POS terminals are often used for remote and temporary locations.
POP
Short for population. One "POP" equals one person. For example, a carrier whose market serves 1 million people is said to offer service to 1 million POPs. In the wireless industry, systems are valued financially based on the population of the market served.
Portable
Portable phones are small, handheld units which can fit in a pocket, briefcase, or purse. Using an attachment, many can be plugged into an automobile cigarette lighter to save battery power. As a smaller, lighter phone, a portable operates at power levels of up to 6/10ths of a watt. Furthermore, digital phones are almost always portable phones. See also Mobile, Transportable.
Protocol
A specific set of rules for organizing the transmission of data in a network.
RF (Radio Frequency)
A frequency well above the range of human hearing.
Roaming
The ability to use a wireless phone to make and receive calls in places outside one's home calling area.
RSA (Rural Service Area)
One of the 428 FCC-designated rural markets across the United States. There are two cellular carriers licensed in each RSA. See also MSA, CGSA.
Service Charge
The amount paid each month to receive wireless service. This amount is fixed and is to be paid regardless of how much or how little the wireless phone is used.
SIM (Subscriber Identity Module)
A computer chip set in a handset that contains information needed to identify the subscriber when connecting to the network, especially for billing purposes.
Smart Card
A credit card-sized card with a microprocessor and memory.
Smart Phone
A phone with a microprocessor, memory, screen and a built-in modem. The smart phone combines the some of the capabilities of a PC on a handset.
SMR (Specialized Mobile Radio)
Private business service using mobile radiotelephones and base stations similar to other wireless services. It is usually used in dispatch applications, such as delivery companies or taxicab organizations. Specialized Mobile Radio is the forerunner of ESMR service. See also ESMR.
SMS (Short Message Service)
A service to send short alphanumeric messages between devices.
Spoofing
An access method that supports a very fast dial-up routine in a switched network that mimics the functionality of a packet switched data network.
Spread Spectrum
A modulation technique, also known as frequency hopping, used in wireless systems. The data is packetized and spread over a range of bandwidth.
Standby Time
The amount of time a fully charged wireless portable or transportable phone can be on before the phone's battery will lose power. See also Talk Time.
Store-and-Forward
The ability to transmit a message to an intermediate relay point and store it temporarily when the receiving device is unavailable.
Synchronization
Also known as "replication," it is the process of uploading and downloading information from two or more databases, so that each is identical.
Talk Time
The length of time one can talk on a portable or transportable wireless phone without recharging the battery. The battery capacity of a phone is usually expressed in terms of "minutes of talk time" or "hours of standby time." When one is talking, the phone draws more power from the battery. See also Standby Time.
TCP/IP (Transmission Control Protocol/Internet Protocol)
The standard set of protocols used by the Internet for transferring information between computers, handsets, and other devices.
Telemetry
A wireless or landline system for the transmission of data (either digital or analog) for remote monitoring.
TDMA (Time Division Multiple Access)
A method of digital wireless communications transmission allowing a large number of users to access (in sequence) a single radio frequency channel without interference by allocating unique time slots to each user within each channel. See also Digital Modulation.
Telecommunications Act of 1996
Signed into law by President Clinton on February 8, 1996, it establishes a pro-competitive, deregulatory framework for telecommunications in the United States.
Third Generation
See 3G.
TMSI (Temporary Mobile Station Identifier)
A mobile station identifier (MSID) sent over the air interface and is assigned dynamically by the network to the mobile station. See also MIN, IMSI
Transportable Phone
Transportable phones, or "bag phones" are essentially car phones with the handset, antenna, and battery packaged together in a carrying case. They can be plugged into a car's cigarette lighter or can operate off of a portable battery pack for use anywhere. Like a mobile phone, transportable phones can operate at up to 3 watts of power. Although technically "portable," the transportable should not be confused with the handheld, one-piece wireless phone. See also Portable, Mobile.
UMTS (Universal Mobile Telecommunications Services)
The European term for wireless systems based on the IMT-2000 standard.
Vocoder
A device used to convert speech into digital signals. See also Digital Modulation.
Voice Mail
A computerized answering service that answers a call, plays a greeting, and records a message. Depending on the sophistication of the service, it also can notify the subscriber, via pager, that he or she has received a call. Also called voice messaging.
Voice-Activated Dialing
A feature that permits one to dial a phone number by speaking to a wireless phone instead of using a keypad. The feature contributes to convenience as well as driving safety.
WAN (Wide Area Network)
A network that uses local telephone company lines to connect geographically dispersed sites.
See LAN and MAN.
WAP (Wireless Applications Protocol)
A proposed protocol for wireless applications. The protocol is designed to simplify how wireless users access electronic and voice mail, send and receive faxes, make stock trades, conduct banking transactions and view miniature Web pages on a small screen.
Wireless
Describing radio-based systems that allow transmission of telephone and/or data signals through the air without a physical connection, such as a metal wire or fiber optic cable.
Wireline Cellular Carrier
The Block "B" carrier. Under the FCC's initial cellular licensing procedures, the Block B carrier is the local telephone company's licensee. The FCC reserved one of the two systems in every cellular market for the local telephone (or "wireline") company. With initial licensing complete, the distinction has slowly disappeared. The local phone company can sell its cellular system to anyone. See also Non-Wireline Cellular Carrier.
WLL (Wireless Local Loop)
A local wireless communications network that bypasses the local exchange carrier and provides high-speed, fixed data transmission.
WML (Wireless Markup Language)
A compact version of the Handheld Device Markup Language. See HDML.
WRC (World Radio Conference)
Formerly known as WARC, or World Administrative Radio Conference, it is an international conference that sets international frequencies.
X.25
A communication protocol for packet switched public data network.