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2.5 G
Refers to wireless telecommunications technology that is more advanced
than 2G but does not meet requirements for 3G.
An example is GPRS (g). Some observers consider
EDGE (g) and CDMA 2000 1k to be 2.5, but officially
they are 3G.
2G
Second Generation
Refers to the second generation of wireless
telecommunications devices which are digital(g)
by nature, as opposed to the first generation analog(g)
devices (cell phones). 85% of all second generation (2G) devices
worldwide are based on the TDMA(g)/GSM
technology patented by InterDigital Communications Corporation.
About 15% of the 2G devices worldwide are based on the Narrowband(g)
CDMA technology largely patented by Qualcomm.
3G
3G Third Generation The "next generation" of Cellular Radio(g) for
mobile telephony. 3G service was initiated in some parts of the
world in 2002 and is expected to be the predominant technology for
wireless communications worldwide in 2007 and beyond. 3G is the
first cellular radio technology designed from the outset to support
wideband data communications just as well as it supports voice communications.
Promoters envision that 3G will be the basis for a wireless information
society where access to information and information services such
as electronic commerce is available anytime, anyplace and anywhere
to anybody. 3G's technical framework is being defined by the ITU(g)
with its International Mobile Telecommunications 2000 (IMT-2000[g])
program.
A brief historical perspective and more detailed
description of the various modes of the 3G standards follow.
Fifteen years ago, cell phones were almost unheard
of. Today they have become a mainline device for voice communication
and are on the verge of meeting new challenges like high-speed data,
videoconferencing, e-mail and, of course, Internet access -- all
for a people "on the move."
The early analog(g)
cell phones are called "first generation." Fairly similar
systems, which repaired some of the deficiencies of analog(g)
are called "digital" or "second generation." The services offered
differ little among cell phone providers, technologies and equipment
manufacturers. That means that telecom providers easily lose customers
to someone else with a better promotional offer. So-called "third
generation(g)
" will give service providers a chance to offer unique services,
thereby reducing churn and leading toward sustained growth.
Witnessing the increasing incompatibility among
telecom technologies in the early 1990's, the international community,
through the United Nations, became intent on providing as much standardization
as possible in what would become third generation (3G) (g)
Task forces have been working diligently for six years to standardize
3G, the next generation of wireless telecommunications.
In spite of the talk about a "3G standard,"
however, no single standard emerged when the framework for new standards
was confirmed in May, 2000. Current radio transmission technologies
differ enough in the details for each system to be attractive to
different telephone companies, each with their own market realities,
customers, applications, and previously installed equipment, besides
the political realities.
The International Telecommunications Union (ITU(g)
has defined five sets of standards specifications with three basic
technologies within the international third generation wireless
standard. These three basic technologies are:
1. TDMA-Only Standard. This standard will be entirely TDMA(g)
, with no cdma(g)
elements at all. This standard includes Digital Enhanced
Cordless Technology (DECT) (g)
and UWC-136, also known as EDGE (g).
This standard is important because it provides an evolutionary path
for both the old analog(g)
Advanced Mobile Phone System (AMPS(g)
and the second generation digital(g) technologies designed specifically
to be compatible with, and correct the deficiencies of, AMPS(g)
This new "economy class" standard would allow relatively speedy
and low-cost development for both analog(g) and second generation
digital(g), although it is officially 3G. This version might also
be described as 2.75G because it is somewhere between the current
second generation and the new third generation(g) (3G) standards.
Clearly, InterDigital has many foundational patents on the fundamental
technology inherent in this new standard and, in fact, worked closely
with other industry leaders in formulating this new standard.
2. CDMA2000(g) The so-called "Qualcomm Standard", is intended
to provide benefits of third generation(g) <../glossary.htm> wireless
while still protecting the heavy investment some telecom providers
have made in Qualcomm's narrowband(g) CDMA ("IS-95"(g) equipment
and systems, most of which are in North America and Korea. This
technology brings current second generation (narrowband(g) CDMA(g)
equipment to third generation(g) broadband features.
3. WCDMA or UTRA Wideband CDMA(g)with FDD (g) and TDD(g)
What almost everyone agrees will be the most widely used approach
to the new, third generation wireless is a combination of wideband
CDMA(g) air interface(g) , frequency division duplexing (g), time
division duplexing (TDD(g) and GSM(g). The latter allows roaming
and is by far the preferred network in over 110 countries, especially
in Europe. A wide variety of worldwide telecom technology and equipment
firms, including almost all the big names, have merged their various
W-CDMA(g) proposals into a new standard. The intention is to take
advantage of WCDMA(g) technology without ignoring the many GSM(g)
(second generation) systems in the world. These
telecom leaders have come up with a technology based on the well-developed
European (ETSI (g) Universal Mobile Telecommunications System (UMTS(g)
<../glossary.htm>). This consensus 3G(g) system is sometimes called
UTRA(g) (for UMTS(g) terrestrial radio access). Because it is compatible
with the existing GSM(g) systems, it is almost certain that this
standard will be, by far, the most popular. It is likely that Qualcomm
will be able to offer little effective competition with its CDMA2000(g)
standard, except in the United States, Korea, and maybe Japan and
China. While evaluating the deployment of WCDMA and CDMA 2000, the
Chinese government is also considering time division synchronous
code division multiple access (TD-SCDMA).
3G3P
The Third Generation Patent Platform Partnership.
The 3G3P has brought together 41 companies
and organizations to quantify just what is meant by fair, reasonable
and nondiscriminatory terms for evaluating whether a patent is essential
and for establishing a fair price, as well as predefining the commercial
terms of the new company. Independent experts, patent lawyers and
technologists will declare what IPR is an essential technology in
3G and assign it a dollar value. The new not for
profit company will also incorporate an appeal procedure. Although
the company's operating brief is decided, it still has no legal
framework, and must wait for the go ahead from regulatory authorities,
including the US Department of Justice.
3G3P was originally referred to as the UMTS IPR (intellectual
property rights) Working Group when this initiative was in the planning
stages under the auspices of ITU. This group
has sometimes been referred to as the UMTS Intellectual
Property Association. This term should not be confused with
3GPP.
3GPP
Third-generation Partnership Protocol
A global cooperative project in which standardization
bodies in Europe, Japan, South Korea and the United States as founders
are coordinating WCDMA(g) issues,
and coordinating the writing of specifications from the WCDMA international
standards of the ITUCg. See also WCDMA(g).
802.11
Air Interface
Communication of one wireless device with another
via radio waves rather than wires or fiber optic lines.
Also see "testing"(g)
Air Interface
Testing
See "testing"(g)
AMPS
802.16
Advanced Mobile Phone System
First Generation (1G)Cellular Radio(g)
standard developed in the USA. It is an analog(g)
system which uses different frequency carriers to create communications
channels in a technique known as Frequency Division Multiple Access
(FDMA). AMPS is still widely used and forms the basis for a number
of other cellular radio standards such as TACS(g)
and D-AMPS(g). Used primarily in North America, Latin America, Australia
and parts of Russia and Asia.
Analog
A form of transmission that is a continuous
wave electrical signal that varies in frequency and/or amplitude
in response to the variations of a physical phenomena such as human
speech or music. In telephony, your voice is captured by a diaphragm
within the telephone which causes a magnet to vibrate creating a
continuously fluctuating electrical signal that is passed through
a wire circuit and received on the other end.
ARIB
Association of Radio Industries and Businesses,
headquarters in Japan. ARIB is designated as "the Realization Center
for Efficient Use of Radio Spectrum" by The Minister of Posts and
Telecommunications in Japan. Visit the
ARIB web site.
ARM
ARM, a leading intellectual property (IP) provider,
licenses high-performance, low-cost, power-efficient RISC processors,
peripherals, and system-chip designs to leading international electronics
companies. ARM also provides comprehensive support required in developing
a complete system. ARM s microprocessor cores are rapidly becoming
the volume RISC standard in such markets as portable communications,
handheld computing, multimedia digital consumer and embedded solutions.
ARM is sometimes referred to as the "Intel" of the processors it
designs and manufacturers. More information is available at http://www.arm.com.
ASIC
Application Specific Integrated Circuit.
Integrated circuits ("chips") which are custom
designed for specialized applications.
ASSP
Application Specific Standard Product
Asynchronous Mode
A method of transmitting data one bit at time
with started bits, stop bits, and parity attached to each information
segment. The 3G standard, WCDMA, is asynchronous mode, while the
3G standard CDMA2000 is synchronous mode. See Synchronous Mode(g)
for comparison
ATM
Asynchronous Transfer Mode
Broadband transmission technology which provides
the backbone of the world's telecommunications network. ATM breaks
information flows into small fixed-length cells of 53 bytes. Cells
of any type of traffic – voice, multimedia, data or video –
can be interspersed with each other. ATM operates at speeds of 25,
155 and 622 Mbps.
Bandwidth
The information-carrying capacity of a communications
channel. Usually expressed in Hertz (cycles per second) for analog
circuits and in bits per second (BPS) for digital(g)
circuits.
Bandwidth on Demand
A means of allocating the minimum required
bandwidth to users in a wireless system depending on their individual
needs. For example, a mobile voice call requires a small amount
of bandwidth, while mobile Internet access requires much more. A
very important feature in both TDMA(g)
and CDMA 3G systems is the allocation of bandwidth in an extremely
efficient manner, increasing the capacity of a wireless system.
InterDigital Communications Corp. (IDCC) claims it has one of the
best "bandwidth on demand" technologies.
Base station
The central radio transmitter/receiver that
maintains communications with a mobile radiotelephone with a given
range.
Base Station
Emulator
A unique device, utilizing TDD(g)
technology, that simulates the performance of the base station in
a wireless system. Originally developed by InterDigital Communications
Corp. (IDCC) to permit easier, less expensive testing of TDMA(g)
subscriber units, it contains core technology applicable to TDMA(g),
GSM(g), PDC(g), and 3G (g)
WCDMA(g) systems including bimodal phones.
This basically tells if a manufacturer's "independently developed
software program" or "handset prototype" will work in conjunction
with the WCDMA air interface specs they have chosen. Although first
tier industry leaders and specialists (like Nokia, Ericsson, Seimens,
Qualcomm, Ubinetics, Agilent) have this "in house" testing capability,
InterDigital says it will make this testing available to any second
or third tier designer/manufacturer, potentially enabling all tiers
a means of quickly determining how their respective system operates
in the WCDMA environment (dropped calls, MOS[g]
- voice quality, interference, modulation strength, battery consumption,
antenna usage, base station controls settings, etc.). Potential
revenue of various firms from testing can be significant ($2 billion
plus is estimated between 2000 and 2004 as multiple companies begin
to prepare new products for the 3g market place.
B-CDMAT
Broadband Code Division Multiple AccessT. InterDigital's
proprietary version of high speed, wideband CDMA. Designed primarily
for fixed (vs. mobile) wireless local loop, many of the B-CDMA specifications
reportedly have been incorporated into the 3G WCDMA standards.
Bluetooth
A new technology designed to be embedded in
electronic devices in order to provide wireless and seamless connections
over short distances. The idea is to provide an easier to use alternative
to the cable-based interfaces currently in use to link computers
and computer peripherals. Other devices in which Bluetooth chips
could be embedded include mobile telephones, personal digital(g)
assistants, headsets and wristwatches.
Bps
bits per second - meaning data transmission
speed, the number of pieces of information transmitted per second.
BRAN
Broadband
A term applied to telecommunications systems
capable of simultaneously supporting multiple information formats
at relatively high speeds such as voice, high-speed data services
and video services on demand. Overall transmission speeds are typically
hundreds to thousands of times faster than those of Narrowband(g) systems. Also called Wideband (g).
Bypass
Usually refers to the practice of avoiding
local telephone companies' long-distance access fees to local operators
by routing traffic from private networks directly to the long-distance
carrier – i.e. bypassing the local carrier. With the advent
of Mobile Satellite Systems(g), bypass may also
now refer to the bypassing of national carriers to establish international
connections.
CATT
China Academy of Telecommunication Technology
CATT is working with Siemens in the development
of third generation wireless TD-SCDMA (g)
technology.
Call Establishment
See Power Ramp-Up(g)
CDMA
Code Division Multiple Access
Technology straddling second generation and
third generation (3G[g]) mobile Cellular Radio(g)
systems. Under CDMA, communications channels are created by assigning
a special coding scheme to information flows. Also called spread
spectrum. Each piece of communication is given a code and then reassembled
at the receiving end. Business Week writes that CDMA spreads
all signals across the same frequency spectrum and assigns a unique
code to each signal. The dispersal signals are pulled out of the
background noise by a receiver which recognizes the code. The technology
is championed by Qualcomm. Inc., who says there are 42 billion useable
codes. CDMA-based second generation cellular radio systems are in
use in parts of Asia and North and South America. New variations
of CDMA provide the base for several third generation cellular systems.
Also see: Multiple Access(g) for distinctions
between CDMA, TDMA, and FDMA, all variations of "multiple access"
(MA)
Newton's Telecom Dictionary says the major benefits
of CDMA technology is increased capacity over analogues systems
and the use of 3 features: (1) a soft hand-off, ensuring that a
code is connected to a new tower before leaving the current one.
(2) variable rate vocoding allowing the most efficient transmission
rate, and (3) multiple signal processing techniques to increase
power central for signal integrity.
Also see: Spread Spectrum(g)
Also see: Synchronization(g)
Also see: code divisim (g) Visit the
CDMA portion of Qualcomm's web site for more information. Qualcomm
is the chief, but not exclusive, proponent of this technology. More-
see 3G standard, a wireless ledger report.
CDMA Development
Group (CDG)
According to Motorola, "The CDMA Development
Group (CDG) is a nonprofit trade association which was formed to
foster the worldwide development, implementation and use of CDMA.
Growing in recognition around the work as the governing CDMA MoU,
the CDG currently represents over 44 companies including many of
the world's largest wireless operators and equipment manufacturers
(e.g. AT&T, GTE, Motorola, Nokia, Qualcomm, Samsung and Sony). Directors
of the CDG are senior officers and executives of member organizations.
The CDG's primary activities include technical development of features
and services, public relations, education and seminars, regulatory
affairs and international development.
CDMA2000
CDMA (code division multiple access) 2000 is
a radio transmission technology for the evolution of Narrowband(g)
cdmaOne/IS-95(g) to 3rd-generation adding up
multiple carriers CDMA 2000 1xRTT is considered to be a 3G standard.
For more information, see the
Third Generation section of the Qualcomm web site . CDMA2000
is generally associated with prime supporter, Qualcomm, although
other industry leaders are also involved with this technology. See
also WCDMA(g) for single carrier/direct spread
technology, the primary competitor of CDMA2000 technology. Visit
the
ITU standards web site for a diagram of the new 3G standards.,
which include CDMA2000. More- see 3G standards, a wireless ledger
report.
CDPD
Cellular digital packet data
AT&T is offering cellular digital packet data
services that provide Internet information over a wireless packet
network to mobile phones.
Cellular Radio
Cellular Radio is the technology that has made
wide scale mobile telephony possible – before cellular radio
the problem with the mobile phone as a concept was how to get large
numbers of users to share small amounts of radio spectrum. Cellular
radio solved this problem by allowing the reuse of the same radio
frequencies by assigning them to cells which were far enough apart
to prevent noticeable interference. Frequency Division Multiple
Access (FDMA[g]) was the basis for first generation
cellular radio systems. Second generation cellular radio systems
- the current generation - use digital(g)
techniques such as TDMA(g), its cousin GSM (g)and
CDMA(g) to support high bit rate voice and limited
data communications. Third generation (3G[g])
systems will support voice and high bit rate data allowing mobile
multimedia applications (see also Narrowband(g),
Wideband(g)). More- "How cell phones
work (how
stuff works)
Circuit-switching
Means of creating telecoms connections by setting
up an end-to-end circuit. The circuit remains open for the duration
of the communication and a fixed share of network resources is tied
up with no one else able to make use of them until the connection
is closed. The main advantage of circuit-switching is that it enables
performance guarantees to be offered. See also Packet Switching(g).
Code Division
A mean of creating multiple circuits on a single
channel by assigning codes to fit a data which are reassembled at
the receiving end combined with Time Division Multiplexing (g).
Compression
See Digital compression(g)
D-AMPS
Digital Advanced Mobile Phone System
TDMA(g)-based second generation
(2G) cellular radio standard originated in North America. Sometimes
D-AMPS is also referred to as TDMA(g)
although it is not the only form of TDMA(g),
with others including GSM(g) and PDC(g).
D-AMPS is widely used throughout the Americas, and uses frequencies
in the 800 MHz and 1900 MHz frequency bands. InterDigital claims
proprietary rights to this technology.
Decoder
A device that restores a signal to its original
form after it has been encoded.
DECT
Digital Enhanced Cordless Telecommunications
A standard for cordless personal telephony
originally established by ETSI, a European standardization body.
DECT(g) is a system for cordless
business communications. It is the least popular of the 3G standards.
More- 3G standards, a wireless ledger report.
Digital
A form of transmission that transforms analog
signals (e.g. speech) into a series of electrical or optical pulses
that represent the binary digits 0 and 1. The first step of a digital
transmission is sampling the analog waveform and converting it into
a stream of numerical data. This data is then converted into a form
such as electronic pulses for a wired network, optical light waves
for transmission over fiber optics or into radio waves for wireless
transmissions. Digital networks are rapidly replacing analog ones
as they offer improved sound quality, secure transmission and can
handle data as well as voice. Digital networks include mobile systems
GSM 900, GSM 1800, GSM 1900, D-AMPS and the cordless DECT(g)
system. CDMA (g) and all 3G systems
(g)
Digital compression
A way of reducing the number of bits in a digital
signal by using mathematical algorithms to eliminate redundant information
thereby reducing the space the signal occupies when being transmitted
or recorded.
DSL
Digital subscriber line
DSP
Digital Signal Processor
A specialized digital microprocessor used to
efficiently and rapidly perform calculations on digitized signals
that were originally analog in form (e.g. voice). The big advantage
of DSP(g) lies in the programmability of the
processor, allowing parameters to be easily changed. Both Texas
Instruments and Infinion Technologies are major DSP producers.
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. For example GSM
900, GSM 1800.
Dual mode
Dual mode mobile phones work on more than one
network (for example, TDMA[g] and
AMPS, GSM and DECT[g]). GSA and
WCDMA (g) also see triple works (g)
EDGE
Enhanced Data Rates for GSM Evolution
An enhanced modulation technique designed to
increase network capacity and data rates on GSM(g)
networks. EDGE, due to be introduced in 2000-2001, promises to provide
a threefold improvement to current data rates without requiring
new network infrastructure. Instead it is based on a major change
in the GSM standard to support 8-PSK (Phase Shift Keying) based
signal modulation as well as existing GSM modulation.
GSM standards bodies have been defining data networking technologies
that build upon GSM. For an excellent, illustrated paper that discusses
the evolution of TDMA(g)-based GSM
technology from its original form through GPRS(g)
and EDGE as it evolves into third generation WCDMA, which will offer
data rates to 2 Mbps., See the Rysavy
Research on the GSM evolution track.
Amy Karam says that in the United States, EDGE technology will bridge
the gap between Time Division Multiple Access (TDMA) networks and
the GSM networks more common in the rest of the world, to provide
a degree of global roaming for wireless users. EDGE is the evolution
of GSM and TDMA into a system capable of a 384-kbits/s data rate.
Edge will allow GSM and TDMA to converge into a global network in
which roaming across international and technological boundaries
is possible. For more see= 3G standard, a wireless ledger report.
Unfortunately, EDGE is limited by a ceiling in transmission spreads
and will not be able to offer high speed
modes, where refers WCDMA or CDMA.
Encoder
A device that encodes the signal before transmission.
Ethernet
The most widely-installed LAN(g)
technology. Standardized as IEEE 802.3, an Ethernet LAN uses Carrier
Sense Multiple Access with Collision Detection (CSMA/CD) protocol
(originally developed to manage radio based data communications
- hence the name Ethernet) running over a coaxial cable or twisted
pair wires. The most commonly installed Ethernet systems are called
10BASE-T and provide transmission speeds up to 10 Mbps. Fast
Ethernet, or 100BASE-T10, provides transmission speeds of up to
100 Mbps and is typically used for LAN backbone systems, supporting
workstations with 10BASE-T cards. Gigabit Ethernet provides an even
higher level of backbone support at 1 Gbps.
ETSI
European Telecommunications Standards Institute
is a nonprofit making organization whose mission is to produce the
telecommunications standards that will be used for decades to come
throughout Europe and beyond. Based in Sophia Antipolis - a high
tech research park in southern France - ETSI unites 773 members
from 52 countries inside and outside Europe, and represents administrations,
network operators, manufacturers, service providers, research bodies
and users. Visit the ETSI
web site.
FDD
Frequency Division Duplex
Full duplex operation by using a pair of frequencies,
one for transmission and one for reception. FDD supports two-way
radio communication using paired radio frequencies, is ideal for
high volume mobile voice traffic, and is the traditional cellular
and PCS radio spectrum allocation format. TDD (g),
or Time Division Duplex, uses a single frequency band to transmit
signals alternately in forward and reverse directions. FDD is ideal
for high volume voice traffic, whereas TDD is ideal for transmitting
large amounts of data such as Internet access in a mobile format.
See: UTRA FDD (g) More- 3G standard, a wireless
ledger report
FDMA
Frequency Division Multiple Access
A method of radio transmission that allows
a large number of users to share access to a group of radio frequency
channels without interference by assigning specific frequencies
within the group of frequencies to each user. See AMPS(g),
Cellular Radio(g)
Frame Relay
High speed transmission method, switching packets
of data through its network to their destination. Access to the
network is via Frame Relay Access Devices (FRADs) which translate
the data (e.g. Ethernet, Token Ring) into frame relay packets. The
network sets up a virtual circuit which is a path to the destination.
Frame relay is more popular in the US than in Europe, but the main
European carriers offer frame relay service. Frame relay can operate
at speeds of up to 45 Mbps, since it is a lightweight system without
error correction, relying on the integrity of the fiber optic hardware.
Frequency
The rate at which an electrical current alternates,
usually measured in Hertz. Frequency equals the number of complete
cycles of current occurring in one second.
FWA
Fixed Wireless Access
Term describing a general means of providing
the last "mile" link to fixed telecommunications network subscribers
through the use of radio technology. FWA is typically deployed in
rural areas where the cost of cabled local loops can be particularly
high and for projects where the rapid deployment of new telecommunications
subscriber connections is particularly important. Also called WLL(wireless
local loop) convert with mobile system
FPGA
Field-programmable gate array
GHz
GigaHertz (billions of Hertz).
Global
Pilot Channel
See Pilot Channel / Pilot Code(g)
Globalstar
Low-Earth-Orbiting (LEO) satellite-based digital communications
system.
GPRS
General Packet Radio Services
Packet Switched(g)
data radio technology for GSM networks. GPRS(g)
connections are always open giving mobile terminal users the same
kind of network availability they may be used to from corporate
networks. There are no set up and clear down times associated with
data calls made via GPRS(g). Terminals can therefore
effectively become a part of the Internet.
GSM standards bodies have been defining data networking technologies
that will build upon GPRS(g). One such technology
is called Enhanced Data rate for GSM Evolution (EDGE) which will
offer a maximum theoretical rate of 384 kbps, though normal operating
speeds will be about half this rate. Beyond EDGE, third generation
cellular systems will eventually offer data rates to 2 Mbps. For
an excellent, illustrated paper on the evolution of TDMA(g)-based
GSM systems to GPRS(g) and then to EDGE and
finally third generation WCDMA, see the Rysavy
Research on the GSM evolution track.
General Packet Radio Service (GPRS) technology is part of the evolutionary
first step toward 3G. Primarily a software upgrade to the Global
System for Mobile Communications (GSM) wireless networks that provide
mobile phone service in much of the world, GPRS provides mobile
users with access to Internet information. It is a natural part
of the migration path to 3G and uses the same base stations as GSM
with a modification of software and the addition of support nodes,
plus a link to a packet data network. Currently, GPRS is in trials
around the world. It is sometimes referred to as 7.5G
The Third Generation Partnership Project (3GPP) (g)
working group of the International Telecommunications Union is working
out the issues surrounding wireless packet voice, such as quality
of service, security and voice quality. That group is also working
with the Internet Engineering Task Force because the issue requires
a blending of the telecommunications and Internet worlds. More:
"How GPs receives work" (How
stuff works).
GPs
Muller 347. More: "How GPs Receives Work" (How
stuff works)
GSM
Global System for Mobile communications
TDMA(g)-based second generation mobile Cellular
Radio(g) technology, originated in
Europe but now used in over 100 countries around the world. GSM
supports voice, data and text messaging and allows roaming between
different networks – which means that GSM users can take their
phones with them to many parts of the world. GSM systems currently
operate at 800 MHz, 900 MHz, 1800 MHz or 1900 MHz. Countries have
been rapidly building up GSM networks, resulting in over 160 million
fully working subscribers in over 125 countries. Eighty percent
of all digital cell phones worldwide are based on GSM/TDMA(g)
technology. InterDigital firsthand claim Motorola and other proprietary
rights to both GSM and TDMA(g) technology.
GSM standards bodies have been defining data networking technologies
that will build upon GSM. One is a technology called GPRS(g).
A further evolution is called Enhanced Data rate for GSM Evolution
(EDGE) which will offer a maximum theoretical rate of 384 kbps,
though normal operating speeds will be about half this rate. Beyond
EDGE, third generation cellular systems will eventually offer data
rates to 2 Mbps. For an excellent, illustrated paper on the evolution
of TDMA(g)-based GSM systems to
GPRS(g) and then to EDGE and finally third generation
WCDMA, see the Rysavy
Research on the GSM evolution track. For information on how
the GSM standard and developed see standard report.
Handoff
inter-cell handoff
The process by which subscribers traveling through a cellular
system coverage area are switched from one cell to another cell
(and different channels) with better coverage for that particular
geographic area. InterDigita. Communications Corp. (IDCC) claims
to have developed a new "seamless hand-over" method of handing over
CDMA calls between cells that requires minimum system overhead and
maximizes CDMA system capacity. This increases the coverage area,
accommodates more users and saves battery life, according to recent
company claims. See also Soft Handoff(g)
more "How cell phones work" (How stuff works)
intra-cell
The process by which subscribers traveling through the coverage
area of a single cell are switched from one sector to another sector
(and different channels) with better coverage for that particular
geographic area. See also Soft Handoff(g)
Hertz
The unit of measuring frequency (one cycle per second). See Integrated
Circuit (g)
HDR (High Data Rate) High Chip Rate TDD-
see widebaned TDD (WTDD)(g)
A high speed, high capacity wireless technology. HDR unleashes
Internet access by providing up to 2.4 Mbps in a 1.25 MHz channel
which is exceptional in systems capable of fixed, portable, and
mobile services. The HDR system is optimized for packet data services,
with a decentralized architecture based on IP protocols/platforms.
HDR's network salability and resource optimization provides maximum
utilization of network and spectrum resources. The compatibility
of this technology with Narrowband CDMA networks provides further
advantages with deployment and optimization costs. Apparently, Qualcomm
continues to lead the development of Narrowband CDMA with the technology
in this versatile wireless data solution. Qualcomm claims that in
conjunction with an existing voice network, or stand-alone data
network, HDR offers a high speed, cost-effective wireless data solution.
For further information, see
Qualcomm's web site section dealing with HDR.
See TDD (g) for an equivalent technology being
developed now by Nokia and InterDigital for third generation applications.
HSCSD
High Speed Circuit Switched Data
Dedicated Circuit Switched(g)
data communications technology for GSM(g) systems
which boosts GSM data speeds from the regular 9.6 kbps to 14.4 kbps
in a single traffic channel and, by using multiplexing(g)
techniques, up to 57.6 kbps. EDGE(g) will boost
HSCSD rates even further. HSCSD capabilities are available on circuit-switched
networks, and should not be confused with packet-switched technologies.
For an excellent, illustrated paper on the evolution of TDMA(g)-based
GSM(g) technology see Rysavy
Research .
HTML
Hypertext Markup Language
Page description language used by designers of web pages to create
information content for the World Wide Web. Markers such as <P>
define page layout features such as New Paragraph. Elements of the
page can also be set using HTML to become hypertext links to information
on the same page or other pages on the web.
IMT-2000 (International Mobile
Telecommunications)
A term used by the International Telecommunication Union, ITU(g),
a United Nations agency, to describe the third generation mobile
telephony standard due to be largely completed in 2000. Can also
be applied to mobile telephone standards that meet a number of requirements
in terms of transmission speed and other factors. See IMT-2000 standards
(g) for a brief description of these
very important standards and a link to a further explanation at
the ITU web site. For a fascinating report on how standards have
been determined, see (standards)
IMT-2000 Standards
The most important work of the United Nations-sponsored International
Telecommunications Union (ITU) (g) standards
setting body has been the determination of international standards
for the third generation wireless communications. Although some
refer to there being "one" standard, in effect there are five specifications
or modes to this standard. The standards reflect a distillation
of the strongest recommendations from various parts of the world
(principally Europe, Asia and the US) and from proponents of the
two major digital wireless technologies: TDMA (g)
with its cousin GSM (g) and CDMA (g).
Work on the standards was 90%+ competed in the Fall of 2000. The
five specifications under the 3G standard include three forms of
CDMA (g) technology: (1) Time Division Duplex
(TDD) (g) and (2) Frequency Division Duplex (FDD)
(g) - both forms of (wideband) WCDMA (g),
and (3) FDD Multi-carrier CDMA (referred to as CDMA2000 (g)).
The standard also includes two forms of TDMA (g)
technology: (1) Digital Enhanced Cordless Telephone (DECT) (g),
and (2) (UWC) IS-136 (g), an evolved form of
the US IS-136 (g) digital cellular standard.
For general information on the very important new international
standards, see:
IMT-2000 standards at the ITU web site . Visit the
ITU standards web site for a diagram of the new standards. More-3G
standard, a wireless ledger report
IMT-2000 Terrestrial Radio Interfaces
The IMT-2000 (g) terrestrial standard consists
of a set of radio interfaces which allow performance optimization
in a wide range of radio operating environments. (The term "terrestrial"
is used as a distinction from other standards for "satellite" interfaces.)
See
diagram of standards at ITU (g) web site.
IMT-DS
International Mobile Telecommunications Direct Spread
One of the five third generation (g) standards
approved by the International Telecommunications Union (ITU) (g).
This is the WCDMA (g) standard also know as
UTRA FDD (g) Visit the
ITU standards web site for a diagram of the new standards.
IMT-FT
International Mobile Telecommunications Frequency Time
An ITU (g) third generation (g)
wireless standard is more commonly known as DECT (g).
Visit the
ITU standards web site for a diagram of the new standards.
IMT-MC
International Mobile Telecommunications Multi Carrier
One of the ITU (g) standards (g) for third
generation (g) wireless more commonly known as
CDMA2000 (g) Visit the
ITU standards web site for a diagram of the new standards.
IMT-SC
International Mobile Telecommunications Single Carrier
An ITU (g) third generation (g)
wireless standard is more commonly known as (UWC) IS-136 (g)
Visit the
ITU standards web site for a diagram of the new standards.
IMT-TC
International Mobile Telecommunications Time Code
A third generation (g) wireless technology based
on both CDMA (g) and TDMA (g),
this ITU (g) standard is more commonly known
as either (UTRA) TDD (g) or TD-SCDMA (g).
Visit the
ITU standards web site for a diagram of the new standards.
Infrastructure
All parts of the wireless network, excluding the subscriber handset.
Includes the MTSO (switch), Base Stations, Cell Sites, and all links
between them.
Interference
Static or unwanted signals producing a distortion of sounds or
images and preventing good reception. See also: Joint Detection
and Interference Cancellation(g)
Integrated Circuit (IC)
A device consisting of a number of connected circuit elements,
such as transistors and resistors, fabricated on a single ship of
silicon crystal or other semiconductor material. Integrated circuits
are categorized buy the number of elements they contain.
Internet
A worldwide network of computer networks in which users at any
one computer can, if they have permission, get information from
any other computer. The idea was conceived by the Advanced Research
Projects Agency (ARPA) of the US government in 1969 and was first
known as Arpanet. Since then it has been demilitarized and commercialized
and augmented by a series of inventions and innovations, not least
of which is the web browser invented by a team led by Tim Berners-Lee
in 1991 at CERN, the European Laboratory for Particle Physics. This
is the basis for the World Wide Web which has been so successful
that it is now often confused in popular conversation with the Internet
itself.
Internet Telephony
See IP Telephony(g)
IP
See TCP/IP(g) district from IP (Intellectual
Property)
IP
Intellectual property, as in patented technology.
See: Intellectual property rights (IPR) (g) District
from IP (Internet Protocol- TCP/IP)
IP Telephony
Also known as Internet Telephony or Voice over IP (VoIP). Use
of Internet Protocol (IP, see TCP/IP(g)) to
carry and route two-way voice communications. IP Telephony can support
telephone to telephone links through suitable adapters but also
voice communications from telephone to IP terminal (such as a PC
with sound card) or from IP terminal to IP terminal. The technique
promises drastically reduced costs to carriers and therefore prices
to end users – but it still suffers problems with quality.
IPR
Intellectual Property Rights
Tony Milbourn, Managing Director, TTP Communications Ltd., Melbourne,
UK puts IPR into context: "Intellectual property is our product;
in the new economy we are selling know-how and design. We need to
create, develop, maintain and protect these intellectual property
rights (IPR). There is a real tension here. Our customers need to
be able to respond fast, to control their destiny, and to add value
to their purchase in various ways. We need to avoid IPR leakage,
which would devalue our product. If we are overprotective, we will
never sell and the customer will never succeed. However, unless
we are careful we will destroy our future business, as our IPR appears
on the Internet free for all. Surely management of IPR is a critical
issue in electronics companies today." See wireless ledger on investing
in intellectual property (g)
IS-41
Inter-network connection protocol for connecting systems based
on both analog and digital US standards. Interim standard 41
IS-54
Original TDMA(g) digital standard.
Implemented in 1992 and then upgraded to the latest IS-136(g)
digital standard in 1996. Interim standard 54.
IS-95/cdmaOne
In July, 1993, the Telecommunications Industry Association (TIA)
(g) adopted a North American interim standard (IS-95) for second
generation (2G) (g) cellular telecommunications
based on Qualcomm's Narrowband CDMA technology. See the
CDMA section of Qualcomm's web site for more information.
IS-136
A digital mobile telephony 3GE standard based on TDMA(g)
technology. See also TDMA(g)
and D-AMPS . It is also called EDGE (g).
ISDN
Integrated Services Digital Network
A fully digital telecommunications network access method which
works over copper wires. There are two types of ISDN, basic rate
and primary rate. Basic rate ISDN provides subscribers with two
64 kbps information channels and a single 16 kbps control channel.
Primary rate provides users with thirty 64 kbps information channels
and a 64 kbps control channel.
ISP
Internet Service Provider(g)
Point of access to the Internet for small business and individual
users. The ISP provides its customers with dial-up access to its
router which relays traffic to web servers on the Internet.
ITU (International Telecommunication Union)
An international organization under the auspices of the United
Nations based in Geneca, Switzerland, is responsible for making
recommendations and establishing standards governing and data communications
systems for public and private. For a report on how International
standards are set see standards.
Joint Detection and Interference
Cancellation
An InterDigital Communications Corp. (IDCC) invention that cancels
out extraneous noise. In a CDMA system everyone talks at the same
time and each person is assigned a code. Envision a party where
each person is using a different language to communicate. If you
know the language of the person you want to speak to, you can cancel
out the other languages in order to communicate with that person.
See also Multiple Access(g), in particular
the "cocktail party" analogy.
KHz
Kilohertz (thousands of Hertz).
LAN
Local Area Network
A LAN is a means of interconnecting computers at relatively high
speed within a relatively small geographic area. Peer-to-peer LANs
assign equal status to all the computers connected to them. A server-based
LAN runs applications and stores data on a computer designated as
the server with the other computers acting as workstations. A LAN
may serve as few as a handful of users or as many as several thousand.
LEO
See MSS(g)
Local loop
A communications link (usually wire), between a telephone subscriber's
location and the local telephone Central Office.
MHz
Megahertz (millions of Hertz).
MMS (Multimedia Messaging Service)
Multimedia Messaging Service is a substantial envolvment from its
producer, SMS (Short Message Service) (g).
Cell phone market leader Nokia (37% market share) is the major proponent
of MMS. Nokia says "The Nokia MMS solution. . . The Nokia MMS
solution gives mobile subscribers with MMS phones the ability to
send and receive text, images, graphics and sound blended into a
single rich message. MMS capable phones can also send multimedia
messages directly to any e-mail address's. The Nokia Terminal Gateway
makes it possible even for users of non-MMS capable legacy GSM terminals
to receive multimedia messages. Legacy-terminals users receive an
SMS notification and can connect to a web site to view their MMS
message." Observers look for MMS to provide an attractive application
for the immense capabilities of 3G (g) technology, which is beginning
in some very limited markets in 2002 and expanding throughout 2003-2004.
Market in Asia and Europe will be the first to experience 3GT WCDMA
(g), on evolution of GSM (g), TDMA (g), GPRS (g), and EDGE (g).
Mobile system
A wireless mobile phone system or network consists of a network
of cells. Each cell is served by a radio base station from where
calls are forwarded to and received from your mobile phone by wireless
radio signals. See FWA, fixed wireless access (g).
Modem
Modulator/Demodulator
Device which converts the digital signals from a computer into
the analogue tones which are compatible with all telephone networks,
and back again. For example, a modem effectively allows computers
to use telephone networks for communication with other computers.
Modulation techniques include a combination of AM (Amplitude Modulation),
FM (frequenting Modulation), and PM (Phone Modulation), also known
as PSK (phone shift keying). Techniques foster compression of signals,
allowing more data to be transmitted in the same period of time.
MSS
Mobile-Satellite Service
A satellite communications system designed principally to support
mobile terminals. Some MSS use Low Earth Orbit (LEO) satellite systems
for their infrastructure. Each LEO satellite has the advantage of
being smaller and cheaper to build and launch than geostationary
satellites. And, because of their lower heights, they can be accessed
more easily by mobile handsets. They can also cover parts of the
world where it would otherwise be uneconomical to provide a telecommunications
infrastructure. MSS operators include Globalstar, Inmarsat, ICO
and Iridium.
Multi-Code Transmission
This technology allows a CDMA system to support high data- rate
communications. It also makes the air interface flexible enough
to provide different data rates to different mobile users on a dynamic
basis. This is a fundamental feature of 3G designs and is part of
the new international 3G standards. InterDigital Communications
Corp. (IDCC) claims that this technology was first developed for
its proprietary B-CDMA fixed wireless designs and has now been adopted
as part of the standards for mobile wireless usage.
Multipath fading
The deflection of a radio signal off obstacles which can cause
interference during signal reception. Multipath occurs when a radio
signal is received directly by an antenna and later the same signal
is received again, reflected from a building or mountain. "Ghosting"
of a TV signal is a form of muiltipath. Under certain conditions,
two or more of the signals can interfere with each other and create
"fading" (a loss of signal) in the communications link.
Multiple Access
A methodology (FDMA, TDMA[g],
CDMA) by which multiple users share access to a transmission channel.
Most modern systems accomplish this through "demand assignment"
where the specific parameter (frequency, time slot, or code) is
automatically assigned when a subscriber requires it. See also:
Bandwidth on Demand(g); Joint Detection
and Interference Cancellation(g);
Power Control(g); Power Ramp Up(g);
Multiplex
A stream of all the digital data carrying one or more services
within a single physical channel.
Multiplexing
The simultaneous transmission of two or more signals on the same
transmission medium.
Narrowband
A term applied to telecommunications facilities originally capable
of carrying only voice, facsimile images, slow-scan video images
and data transmissions at kilobit speeds until recently. Narrowband(g)
facilities, unlike broadband facilities, could not handle full-color,
full-motion video images or data transmissions at megabit speeds.
The term is commonly applied to voice-grade analogue facilities
and to digital facilities operating at speeds of less than 1.544
Mbps.
NMT
Nordic Mobile Telephone
One of the earliest commercial Cellular Radio(g) systems developed jointly by organization in the
countries of Northern Europe, Denmark, Finland, Iceland, Norway
and Sweden. It comes in two variants – NMT450 – the original
specification operating in the 450 MHz band and particularly suited
to covering wide areas with low usage densities – and NMT900
– introduced in the late 1980s and designed to support handheld
portable devices in urban environments.
NTDD
Narrowband TDD. (See TDD) Qualcomm has made remarkable programs
in developing Narrowband communication into a very high quality
service comparable in my respect with wideband (g).
Open SystemC
The Open SystemC Initiative is based on an "open community licensing
model," which means that the underlying source code that forms the
platform of SystemC is available to the community at large, without
charge. (Linux, Gnu, Apache, Netscape's Mozilla and Sun Microsystems'
Jini are examples of other types of software available through similar
innovative licensing models. The Open SystemC Initiative takes the
best aspects of each of these models.) The idea behind open community
licensing is to create some useful and valuable source code, and
then publish it so that anyone can access it. When others identify
bugs that they can fix or otherwise improve the source code, they
can do so themselves rather than lobby the "owner" of the software
or a formal standards organization for remedial patches or improvements.
With hundreds or thousands of people sharing access and a common
motivation to advance the quality and functionality of the source
code, improvements and new capabilities can happen very quickly
- far faster than could be accomplished by a single company, no
matter how large. Open community licensing, then, is the opposite
of the proprietary model widely favored throughout the software
industry. Closed, proprietary source code models essentially say
that "We own the source code. It's closed and nobody else can touch
it or have any rights to improve it. You'll never see the source
code, but we'd be delighted to license or sell you the object code."
Open SystemC is a cooperative effort that leverages the combined
technology and user experience of Synopsis, CoWare and Frontier
Design. This initiative has established a modeling platform that
enables, promotes and accelerates system-level CO-design and IP
exchange. The SystemC community consists of a large number of system,
semiconductor, IP, embedded software and EDA companies. Industry
leaders committed to Open SystemC include Texas Instruments, Motorola,
Lucent, Sony and CoWare
For further information on Open SystemC, see the
CoWare Site's System C Section. CoWare is one of the founders
of the industry coalition supporting this initiative.
OTA
Over the air (as opposed, for example, to something like synchronization
within the desktop alone).
Packet Data
Information to be transmitted is broken down into digital "packages"
or "packets" of bytes for more efficient use of radio spectrum.
InterDigital Communications Corp. (IDCC) claims to have developed
an extremely efficient way of transporting packet data over a radio
system, increasing radio system capacity. InterDigital says this
method is now included in the new international 3G standard as an
essential part of the TDD(g) air interface Portugal.
Also see: Packet Switching(g)
Packet Switching
Means of creating connections by breaking up the information to
be sent into packets of bytes, sending them along a network with
other information streams and reassembling the original information
flow at the other end. The main advantage of packet-switching is
that it makes very efficient use of fixed capacity. The disadvantage
is that the quality of service of an information channel cannot
be guaranteed. See also Circuit Switching(g).
InterDigital Communications Corp. (IDCC) claims to have developed
an extremely efficient way of transporting packet data over a radio
system, increasing radio system capacity. InterDigital says this
method is now included in the new international 3G standard as an
essential part of the TDD(g) air
interface protocol.
The fundamental difference between a packet-based approach and a
circuit-switched approach to transferring data is the concept of
sharing channels. Thus, according to Lane Schaller and Jim Kamke,
the move to IP is the migration from dedicated channels to shared
channels. Rather than move information across one dedicated channel
as circuit-based networks do, packet-based networks move it across
several different nondedicated channels. Information is transmitted
by squeezing packets of data into unused channel space.
For wireless carriers, using a packet-based approach is an ideal
way to increase capacity. Today, because wireless transmissions
are based on circuit technology, every time a user pauses when speaking,
a carrier in theory is losing money because that pause could be
filled by a burst of data for which the carrier could charge. However,
the move to nondedicated channels also results in challenges. The
biggest is that there is no longer a guaranteed data transfer pipe.
Handsets must now support more complex handshakes with wireless
base stations to ensure that the data is transferred correctly
Path Diversity
Motorola explains "path diversity" as follows: "With radio communications,
there is usually more than one radio frequency (RF) path from the
transmitter to the receiver. Therefore, multiple versions of the
same signal are usually present at the receiver. However, these
signals, which have arrived along different paths, are all time
shifted with respect to each other because of the differences in
the distance each signal has traveled. This "Multipath" effect is
created when a transmitted signal is reflected off of objects in
the environment (buildings, mountains, planes, trucks, etc.). These
reflections, combined with the transmitted signal, create a moving
pattern of signal peaks and nulls....
"When a narrow band receiver moves through these nulls there is
a sudden drop in signal strength. This fading will cause either
lower, more noisy speech quality or, if the fading is severe enough,
the loss of signal and a dropped call. "Although Multipath is usually
detrimental to an analog or TDMA signal, it is actually an advantage
to CDMA, since the CDMA rake receiver can use Multipath to improve
a signal. The CDMA receiver has a number of receive "fingers" which
are capable of receiving the various Multipath signals. The receiver
locks onto the three strongest received Multipath signals, time
shifts them, and then sums them together to produce a signal that
is better than any of the individual signal components. Adding the
Multipath signals together enhances the signal rather than degrading
it." Also see Multipath Fading(g)
PCN
Personal Communications Network
A digital wireless radiotelephone network utilizing low-powered,
wireless telephones, data terminals and microcell base stations
connected to the public network.
PCS
Personal Communications Service
FCC terminology describing intelligent, digital wireless, personal
two-way communications via PCN.
PDC
Personal Digital Communications
TDMA(g)-based second generation
Cellular Radio(g) technology originated in, and mainly used in,
Japan. PDC-based services operate in the 800 MHz and 1500 MHz frequency
bands.
Picocellular
A cellular system based on very small cells, typically serving
users within a 20 to 250 foot radius of the base station. Also see
TDD (g) which will rely heavily apon Pico cell systems.
Pilot
"Pilot" (as in "pilot code") is terminology for a signal that
carries no information other than the very fact of it's existence
plus the timing inherent in producing any signal. A key element
of virtually every CDMA system.
Also see: global pilot channel(g)
Platform Based Design
Basically, a system on a chip (SoC) containing a "library"
of hardware and software building blocks. Offered by the semiconductor
industry, PBD is a silicon architecture and IP (intellectual property)
with enough flexibility to offer families of products for given
applications (cell phones, digital camera, etc.) PBD limits IP to
certain technologies it owns r has licensed, while offering the
flexibility to meet the needs of the semiconductor's customers.
The best PBDs will be those that enable the greatest customer flexibility
at a reasonable cost to the SoC ship maker. Platform creation requires
the semi designers to concentrate first on the interfaces between
the architectural components and then later on the functional blacks
appropriate to the specific needs of the customer. Successful implementation
of a PBD system on a chip requires years of planning and design.
See Pete Hardee, "The Reality of IP Reuse"
Pilot Code (Global Pilot Channel)
A key element of virtually every CDMA system. It is a reference
signal transmitted by the base station that allows reliable and
robust communications by all mobile users. Now an essential part
of the new international 3G standard, InterDigital Communications
Corp. (IDCC) originally used this technique as part of its proprietary
broadband CDMA (B-CDMA) (TM) air interface.
Power Control
A very important mechanism used in CDMA systems to control how
much power is transmitted by and directed to each user. This must
be precise to keep the signal clear and strong and to maximize system
capacity. InterDigital Communications Corp. (IDCC) claims to have
developed superior power control techniques to maximize system capacity
and minimize signal interference and degradation.
Power Ramp-up (and Call Establishment)
In CDMA systems, it is critical that no one user transmit more
power than is required to establish and maintain a call to avoid
interference with other callers. InterDigital Communications Corp.
(IDCC) claims to have invented a ramp-up scheme which is included
in the new international 3G standards. It allows a user to enter
a system at a low power level and increase it gradually until the
call is recognized by the base station.
Processing gain
A "figure of merit" for CDMA (spread spectrum[g])
systems which relates the information data rate to the radio spectrum
bandwidth. In general, the higher the processing gain, the more
immune the CDMA system is to interference.
Protocol Stack
A protocol is a group of rules which determine the format of communications
exchanged between the cell phone (or other device) and its user
and between the devise and the base station (cell tower). Imagine
using your cell phone. You push the power button, touch the number
button, push the send button, then listen for ringing and an answer.
The person you called says "Hello," as do you. And the
conversation begins. When you do this you follow a protocol, a set
of rules which enables a call to go through.
When cell phones communicate with base stations and then base to
stations with other base stations, or with another cell phone, transferring
voice or data, they follow a protocol. Every sound, every piece
of data, every signal is specifically defined. In Wireless Communication,
a photocell, then, is a highly specific group of procedures, or
conversations or rules relating to how data is formatted, timed
and interpreted in the air interface between the base station and
the cell phone or other terminal. Without such a standard procedure
devices and base stations would not be able to understand the wireless
communicators between them.
The protocol also establishes a mathematical measurement which
determines if the block or pocket of data has come through accurately.
If not, it asks for a retransmission until it understands.
A protocol stock is a set of software modals that combine to produce
the software enabling the protocol to work, i.e. to facilitate communication
via radio waves through the air. It is called a stock because the
modules of software are piled on top of each other. The communication
process stocks of the bottom (first layer) of the pile, working
itself up three layer two, three etc.
InterDigital investors are particularly interested in protocol
stock technology because InterDigital, a wired leader in patented
air interface technology, has and exclusive 10 year partnership
with wireless chip industry leader. Infineon technology to provide
layers 2 and 3 for Infineon's protocol stock for 3G WCDMA (FDD and
level mode GPRS/FDD. For more information see: InterDigital-Infineon
partnership).
For a report in the importance of intellectual property (like the
software in protocol stocks) see: IRR (g)
PSTN
Public Switched Telecom Network
QoS
Quality of service
RAM
Random Access Memory
The primary memory in a computer. Memory that can be overwritten
with new information
RAN
Radio access network
Receiver
1. Any device which receives a transmitted signal. 2. Any portion
of a telecommunications device which decodes an encoded signal into
its desired form. The initial standards for 3G WCDMA (g)
mobile telecommunication. Approved in 1999, subsequent releases
are supplementary. The release 99 standards but are compatible with
it. I.e. release 4, release 5
Repeater
Receives radio signals from the base station. They are then amplified
and retransmitted to areas where radio shadow occurs. Repeats also
work in the opposite direction, i.e. receiving radio signals from
mobile telephones, then amplifying and re-transmitting them to the
base station.
RF
Radio frequency
RISC Processor
Reduced Instruction Set Computing
InterDigital plans to offer a highly competitive replacement for
the RISC processor as part of their System on a chip (g),
currently under development.
RNT
Remote Network Terminal
Roaming
Using your cellular phone in an area outside that served by your
"home" cellular. Roaming often incurs extra charges.
Router
A device, or in some cases software in a computer, that determines
the next network point to which a packet should be forwarded on
its way to its destination. Typically, a packet will travel through
a number of network points with routers before arriving at its destination.
RTL
register transfer level
Satellite phone
They will operate both on either GSM/AMPs networks, and via satellite,
in areas where there is no coverage.
SDH
Synchronous Digital Hierarchy
A standard for digital signal transmission within transport networks.
Before SDH, networks were extremely rigid and creating a new link
between two points was time consuming. It could take months to set
up new services. In the late 1980s operators and suppliers standardized
first on SONET and then SDH standards for optical transmission.
By using add/drop multiplexes new signals can be added to or dropped
from the network quickly and easily. The network can then be monitored
centrally, adding to both flexibility and reliability. When a fault
does occur, the traffic can be rerouted so quickly that the user
does not even realize there was anything wrong.
Service provider
A company that provides services and subscriptions to telephone,
mobile phone and Internet users.
Signal
A sequence of electrical impulses or radio waves transmitted or
received. Also see: Power Control(g)
and Joint Detection and Interference Cancellation(g).
Signal Booster
Compensates for loss of effect (weakening of the signal in the
coaxial cable) between the outer antenna and the phone. Applies
to both incoming and outgoing signals.
SIM card (Subscriber Identity Module card)
a small printed circuit board that must be inserted in any GSM-based
mobile phone when signing on as a subscriber. It contains subscriber
details, security information and memory for a personal directory
of numbers.
Simplex (Sx)
Operating a channel in one direction only with no ability to operate
in the other direction. For example one side of a telephone conversation
is all that could be carried by a simplex line.
SMS (short message service)
available on digital networks allowing messages of up to 160 characters
to be sent and received via the network operator's message center
to your mobile phone. 360 billion SMS messages are expected to be
communicated in 2002. Also see: MMS (g)
Sometimes called the "operator"
Soft Handoff
With traditional hard hand-offs, Motorola explains, "the mobile
drops a channel before picking up the next channel. When a call
is in a soft handoff condition, a mobile user is monitored by two
or more cell sites and the transcoder circuitry compares the quality
of the frames from the two receive cell sites on a frame-by-frame
basis. The system can take advantage of the moment-by-moment changes
in signal strength at each of the two cells to pick out the best
signal.
"This ensures that the best possible frame is used in the CDMA
decoding process. The transcoder can literally toggle back and forth
between the cell sites involved in a soft handoff on a frame-by-frame
basis, if that is what is required to select the best frame possible.
"Soft hand-offs also contribute to high call quality by providing
a "make before break" connection. This eliminates the short disruption
of speech one hears with non-CDMA technologies when the RF connection
breaks from one cell to establish the call at the destination cell
during a handoff. Narrow band technologies "compete" for the signal,
and when Cell B "wins" over Cell A, the user is dropped by cell
A (hard handoff). In CDMA the cells "team up" to obtain the best
possible combined information stream. Eventually, Cell A will no
longer receive a strong enough signal from the mobile, and the transcoder
will only be obtaining frames from Cell B. The handoff will have
been completed, undetected by the user. CDMA hand-offs do not create
the "hole" in speech that is heard in other technologies...
"CDMA also provides for "softer" hand-offs. A "softer" handoff
occurs when a subscriber is simultaneously communicating with more
than one sector of the same cell."
Softswitch
A technology developed to help wireless data networks transition
toward 3G (g) is the software-based packet switch,
sometimes called a softswitch. This is critical for voice-over-packet
traffic. A softswitch is essentially software that performs the
functions of a telephone switch. It replaces the circuit switch,
emulating many of its functions in directing voice traffic but adding
flexibility and features unique to packet traffic. Instead of the
point-to-point traffic direction of a circuit switch, a softswitch
can function almost like an Internet Web site, bringing together
content from a wide variety of sources to provide new services to
users, such as access to online address and phone books that are
network-based, so they can be accessed from anywhere. Most major
telecom vendors have some form of deployment of this technology
in mind.
Specialized Mobile Radio (SMR)
A private, business radio service utilizing mobile radio telephones
and base stations. Usually used for fleet dispatch (taxis, etc.).
Spectrum efficiency
A measure of the quantity of users or services that can be simultaneously
supported by a limited radio frequency bandwidth in a defined geographic
area.
Speech encoding
Utilizing signal processing techniques to convert an analog voice
waveform into a digital bit-stream. The digital bit-stream can then
be transmitted over communications or data networks.
Spread spectrum
A method of transmitting a signal by "spreading" it over a broad
range of frequencies (using a compatible receiver to reassemble
the signal). This provides reduced interference (see "processing
gain") and can increase the number of simultaneous users within
a radio frequency band. More- "How cell phones work" (how
stuff works)
Standards for third generation wireless
telecommunications
See IMT-2000 Standards (g). Also
see 3G standards, a wireless ledger report.
Symbian
A joint venture between Ericsson, Motorola, Nokia and Psion aimed
at assuming a leadership role in the rapidly expanding Wireless
Information Device market. Symbian is developing the operating system
EPOC. See also symbian.com
Synchronization
Motorola describes synchronization this way: "In the final stages
of the encoding of the radio link from the base station to the mobile,
CDMA adds a special "pseudo-random code" to the signal that repeats
itself after a finite amount of time. Base stations in the system
distinguish themselves from each other by transmitting different
portions of the code at a given time. In other words, the base stations
transmit time offset versions of the same pseudo-random code. In
order to assure that the time offsets used remain unique from each
other, CDMA stations must remain synchronized to a common time reference.
"The primary source of the very precise synchronization signals
required by CDMA systems is the Global Positioning System (GPS).
GPS is a radio navigation system based on a constellation of orbiting
satellites. Since the GPS system covers the entire surface of the
earth, it provides a readily available method for determining position
and time to as many receivers as are required."
Synchronous
Type of transmission in which the transmission and reception of
all data is synchronized by a common clock and the data is usually
transmitted in blocks rather than individual characters. Can also
mean that the data stream has the same capacity in both directions.
Synchronous mode
Standard for data transmission - data is transferred without start
and stop bits together with a clock signal to synchronize the receiver.
This mode gives higher data throughput than asynchronous mode, but
can be less secure. For comparison see: Asynchronous Mode(g)
System on a Chip (SOC)
The embodiment of a single silicon ship of the essential component
s that components the operational core of a digital(g)
system.
SystemC
See: Open SystemC(g)
TACS
Total Access Communications System
A first generation Cellular Radio(g)
system which is a derivative of AMPS(g). Designed
originally for the UK market but later adopted in many countries
across the world including Hong Kong and Japan, TACS improved upon
AMPS by offering features necessary to more densely populated markets.
TCP/IP
Transmission Control Protocol/Internet Protocol
Collective name for the set of protocols on which the Internet
is based. TCP and IP are the best known of this set, but they are
by no means the only ones. TCP guarantees that every byte sent from
one port arrives at the other in the same order and without duplication
or loss. IP assigns local IP addresses to physical network addresses
providing a structure which can be recognized by Routers(g).
Other members of the TCP/IP family include the Telnet protocol which
allows a remote terminal to log in to another host, the Domain Name
System (DNS) which allows users to refer to hosts by name rather
than having to know their numeric IP addresses, the File Transfer
Protocol (FTP) which defines a mechanism for storing and retrieving
files, and HyperText Transfer Protocol (HTTP) which allows information
to be transferred from host computers to computers equipped with
web borrowers.
TD-SCDMA
Time Division Synchronous Code Division Multiple Access
One of the new third generation standards approved by the ITU
(g). It has been developed in China by the China
Academy of Telecommunication Technology (CATT) and engineers from
Germany's Siemens as a hybrid based on both TDMA (g)
and CDMA (g) technology that, presumably, would
not require use of patents held by San Diego based Qualcomm (which
insists on very high royalties for its technology). Nokia is also
working on this technology. The engineering is related to the Time
Division technology pioneered by InterDigital, a partner with Nokia
in developing Time Division Duplexing (TDD) (g)
in conjunction with wideband CDMA (WCDMA) (g).
Siemens discusses its part in the development of TD-SCDMA technology
on it's
web site. Visit the
ITU standards web site for a diagram of the new standards. Reliable
observers believe that 70% of InterDigital discusses it at __ IDCC's
patented TDD (g) technology is applicable to
TD-SCDMA, making InterDigital a key IPR player in the TD-SCDMA 3G
standard. The industry association for TD-SCDMA is the TD-SCDMA
forcom
TDD
See: Time Division Duplex (g)
TDMA
Time Division Multiple Access
TDMA is a general approach to creating second generation mobile
Cellular Radio(g) systems where communications
channels are created by assigning time slots to information flows.
TDMA is the base technology for the D-AMPS(g),
GSM(g) and PDC(g) digital cellular radio systems. See also IS-136
and D-AMPS . See also Multiple Access(g)
as in "Time Division Multiple Access"
Telco
Telecommunications operator or carrier
Test Benches
See: testing
Testing
All designs of wireless telecommunications devices must be thoroughly
tested to validate their air interface(g)
capabilities ((dropped calls, MOS(g) - voice
quality, interference, modulation strength, battery consumption,
antenna usage, base station controls settings, etc.) Testing ideally
uses a base station emulator(g),
a unique device, utilizing TDD(g) technology, that simulates the
performance of the base station in a wireless system. Originally
developed by InterDigital Communications Corp. (IDCC) to permit
easier, less expensive testing of TDMA(g) subscriber
units, it contains core technology applicable to TDMA(g),
GSM(g), PDC(g), and 3G WCDMA(g)
systems including bimodal phones. This testing hardware and software
basically tells if a manufacturer's "independently developed software
program" or "handset prototype" will work in conjunction with the
WCDMA air interface specs they have chosen. Although first tier
industry leaders and specialists (like Nokia, Ericsson, Seimens,
Qualcomm, Ubinetics, Agilent) have this "in house" testing capability,
InterDigital says it will make this testing available to any second
or third tier designer/manufacturer, potentially enabling all tiers
a means of quickly determining how their respective system operates
in the WCDMA environment . Potential revenue from testing can be
significant ($2 billion plus is estimated between 2000 and 2004
as multiple companies begin to prepare new products for the 3g market
place. TETRA- Terrestrial Transed Radio. A TDMA (g)
based standard of ETSI (g) (European Telecommunication
standards institute. Typically and in communications for fleets
of vehicles such as taxicabs, fire trucks, police and emergency.
Third Generation
See 3G(g)
TIA
Telecommunications Industry Association (USA)
TIA is a full-service national trade organization with membership
of 1000 large and small companies that provide communications and
information technology products, materials, systems, distribution
services and professional services in the United States and around
the world. The association's member companies manufacture or supply
virtually all of the products used in global communication networks.
TIA represents the telecommunications industry with its subsidiary,
the Multimedia Telecommunications Association (MMTA), in conjunction
with the Electronic Industries Alliance (EIA). Visit the TIA
web site.
Time Diversity
Motorola explains :time diversity" this way: "CDMA systems use
a number of forward error correcting codes, followed by interleaving.
"Error correction schemes are most effective when bit errors in
the data stream are spread more evenly over time. By separating
the pieces of data over time, a sudden disruption in the CDMA data
will not cause a corresponding disruption in the voice signal. When
the frames are pieced back together by the decoder, any disrupted
voice data will have been in small pieces over a relatively longer
stretch of the actual speech, reducing or eliminating the impact
on the voice quality of the call. "Interleaving, which is common
to most digital communication systems, ensures that contiguous pieces
of data are not transmitted consecutively. Even if you lose one
small piece of a word, chances are great that the rest of the word
will get through clearly." Also see Path Diversity(g)
for comparison.
Time Division Duplex (TDD)
An ITU (g) third generation (g)
wireless standard based on both TDMA (g) and
CDMA (g) technologies. InterDigital and Siemens
are the primary IPR (g) holders for this technology
of duplexing by using a single frequency divided by time. The TDD
format operates by using a single frequency band to transmit signals
alternately in the forward and reverse direction. In the TDD scheme,
the relative capacity of the forward and reverse links can be altered
in favor of one direction (usually the forward). This is accomplished
by giving a greater time allocation to forward transmission intervals
than reverse by allocating more time slots. This asymmetry is useful
for communication processes characterized by unbalanced information
flow. One important example of this technique is wireless Internet
access in which users typically enter short messages and receive
large information payloads. Both FDD (g) and
TDD are full duplex communication methods. TDD operates by toggling
transmission directions at the basic timing level. This toggling
takes place very rapidly and is imperceptible to the user. TDD can
therefore support voice and other balanced communication services
as well as asymmetric services, even handling a dynamic mix of both.
Also see a related technology, TD-SCDMA (Synchronous Time Division-Code
Division Multiple Access) (g) Visit the
ITU standards web site for a diagram of the new standards. Two
firms own almost all the intellectual property rights (patents)
for TDD: InterDigital Communication and Siemens. NOkia, recognizing
InterDigital's extensive experience with the technology, has contracted
with InterDigital to develop Nokia's entire TDD suite for its 3G
applications, beginning to end. International standards are being
developed in 200-2003. An excellent article on wideband TDD is "How
to Solve Your 3g 'Hot Spot' Problems" by Mark Memmo, Exec.
V.P. of InterDigital. Observers believe InterDigital for more patented
technology in the standards, to date, their and other firms. Lemmo
writes:
"It is important to note that FDD and TDD are complementary
rather than competitive technologies. The classical deployment strategy
for cellular networks, which will also be adopted for 3G implementation,
is hierarchical. In the first phase, large macro cells will be installed
to provide the maximum coverage possible. Typically such cells in
3g will have coverage areas of up to 5km and will be used for urban,
suburban and rural service provision. In the second phase, micro
cells with coverage in areas of high traffic density. FDD technology
will be used for both macro and micro cell deployment.
"The third phase involves the deployment of pico cells with
coverage areas of up to 100 meters. It is in this phase of deployment
that TDD will used.
"TDD is optimized for the high data rats that will be required
for gees traffic hotspots. The majority of this data traffic is
likely to comprise Internet or intranet access with is highly asymmetric,
with high bandwidth required in the downstream direction and minimal
bandwidth upstream. TDD offers an optimal solution for such asymmetric
traffic patterns. TDD, for example, can be configured to proved
384kbps downstream, in the direction to the major data traffic movement,
and 54kbps upstream, where the traffic largely composes requests
for information and acknowledgments. FDD on the other hand is symmetrical,
with equal data bandwidth in both directions. Thus TDD offers a
very adaptable and flexible solution for high data rates and it
provides operators with greater capacity in their networks. . .
"The key issue for operators is, of course, how can they generate
revenues from the deployment of TDD? First, and most obviously,
the provision of high bandwidth in areas of high user demand will
generate service revenues. The capability to download large amounts
of data form the Internet or a corporate Internet whilst waiting
in an airport lounge or hotel room, will be a tremendous boon to
the global business community and they will certainly use such a
capability extensively.
"(The services which TDD makes possible) offer considerable
benefits to operators. Firstly, new revenue streams in terms of
payment for advertising from retailers would be opened up. Airtime
usage, and hence revenues, from subscribers would be increased as
they surfed the system searching for particular items or special
bargains.
"The most significant feature of such services is that they
will be seamless. The user's tri-mode terminal will switch transparently
into TDD mode immediately on entering the coverage area of the pico
cell within the shopping mall or supermarket. No conscious effort
would be required by the user. This represents an important service
differentiate for traditional mobile operators over potential competitors
who may be trying to deliver such services using other technologies
such as BRAN (g) or wireless LAN (g).
The seamlessness offered by the tri-mode phone and TDD would enable
the traditional operator to win the traffic hotspot business, using
spectrum that he already owns and technology, TDD, that is already
incorporated into his network.
"The main focus of the standardization activity first within
ETSI (g) and later 3GPP (g)
has been very much on completing the specification of the FDD elements
of UMTS. The reason for this pressure is obvious, the launch date
for 3G services is 2002 and it is important for credibility of 3G
that this timeline is adhered too.
"However, as has already been pointed out, standards groups
are continuing to work on TDD standardization, in particular on
the air interface (g) and on layer 2/3
protocol stacks (g). The FDD technology
is now in the field trial phase and TDD trails are planned to start
within twelve to eighteen months. Siemens, which is focusing much
of its 3G development activity on TDD, is planning a TDD trial in
South Africa in the near future. Although other major vendors are
working to achieve the FDD deadline, they are also developing TDD
solutions.
"The gap between the launch of WCDMA (g),
FDD 3G networks and the advent of TDD was planned from the outset.
Given the hierarchical rollout strategy outlined earlier - macro,
micro, pico- TDD will not be required in the first phase of deployment
where the main aim will be raped, widespread coverage via FDD. As
3G matures, and the demand for additional, focused capacity and
higher data speeds increases, TDD will be ready and waiting in the
wings ready to meet the needs of operators and subscribers."
More- 3G standards, a wireless ledger report. Also see NTDD (Narrowband
TDD) (g) WTDD (wideband TDD) (g)
and TD-SCDMA (g).
Time Division Multiplexing (TDM)
A means of creating multiple circuits on a single transmission
channel by rapidly connecting terminals one at a time in a recurring
time ordered sequence.
Triple mode
A combined analog and digital mobile phone. Allows operation of
the phone in the existing analog system frequency (8000MHz) and
in both digital frequencies (800MHz and 1900 MHz). In the US, 2G
cell phones are typically triple mode analogue- TDMA (g),
CDMA (g). For 3G, triple mode may refer to GSM-FDD-TDD(g).
Turbo coding
An advanced coding technique in 3G systems which allows the high
data rate channels to be transmitted at lower power than convolution
coding, and thus allows more users per cell. Turbo coding is part
of the new international standards for 3G. Qualcomm, Nokia and InterDigital
are all using turbo coding in their 3G designs. Reportedly, InterDigital
has been the most active participant in suggesting various turbo
coding schemes to the 3GPP standards setting bodies. Also see
power control.
Twisted Pair
Two insulated copper wires twisted together with the "twists"
or "lays" varied in length to reduce potential signal interference
between the pairs. Where cables comprise more than 25 pairs, they
are usually bundled together and wrapped in a cable sheath. Twisted
pair is the most commonly used medium for connecting telephones,
computers and terminals to PABXs, supporting speeds up to 64kbits/sec.
UMTS
Universal Mobile Telecommunications System
A function of ETSI (European Telecommunications Standards Institute)
(g), the Universal Mobile Telecommunication
System (UMTS) makes possible a wide variety of mobile services ranging
from messaging to speech, data and video communications. Its goal
is to take mobile communications well beyond the current range of
fixed telephony, penetrating the population to the extent of one
UMTS terminal to every active citizen. More see 3G standards, a
wireless ledger report.
UNIX
A computer operating system. UNIX is designed to be used by many
people at the same time and has TCP/IP built-in. It is a very common
operating system for servers on the Internet.
UTRA
UMTS (Universal Mobile Telecommunication System ) Terrestrial
Radio Access The ETSI (European Telecommunications Standards Institute)
(g) work on radio interface for third generation
(g) mobile telecom systems is designated UTRA.
Also refereed to as WCDMA (g).
UTRA FDD
See: FDD (g)
Frequency Division Duplexing technology recommended by UTRA (g).
UTRA is UMTS (Universal Mobile Telecommunication System ) Terrestrial
Radio Access. One of the five third generation standards approved
by the International Telecommunications Union (ITU) (g).
This is the WCDMA (g) standard also know as
IMT-DS (International Mobile Telecommunications Direct Spread) (g)
Visit the
ITU standards web site for a diagram of the new standards.
UWC
Universal Wireless Consortium
Body of vendors and operators promoting and implementing the 3G
IS-136(g) digital standard. Also
called EDGE (g) is specifying the future development
of the standard and facilitating roaming agreements between IS-136(g)
operators.
Validation Process
See: Testing(g)
Voice Activity Detection
Voice activity detection is a variable which helps to increase
the capacity in CDMA systems through the use of variable rate vocoders.
Motorola explains: "In a typical phone conversation a person is
actively talking only about 35% of the time. The other 65% is spent
listening to the other party, or is quiet time when neither party
is speaking. The principle behind the variable rate vocoder is to
have it run at high speed, providing the best speech quality, only
when voice activity is detected.
"When no voice activity is detected, the vocoder will drop its
encoding rate, because there is no reason to have high speed encoding
of silence. The encoded rate can drop to 4, 2, or even 1 kbps. Thus
the variable rate vocoder uses up channel capacity only as needed.
Since the level of "interference" created by all of the users directly
determines system capacity, and voice activity detection reduces
the noise level in the system, capacity can be maximized."
VoIP
See IP Telephony(g)
VPN
Virtual Private Network
Looks for all intents and purposes like a private network but
is actually just access to a shared network. Careful management
and guarantees of quality of service levels ensure that corporate
customers get the privacy and facilities they want but at a lower
cost.
WAP
Wireless Access Protocol
WAP is being jointly developed in the mainstream of Internet standardization
activities, with the broad support of many vendors. It provides
the basis for a whole host of new wireless information applications
by offering a gateway between the Internet and mobile telephones.
If an application can be put on the Internet, it can be made available
to mobile terminal users through WAP.
WCDMA
Wideband Code Division Multiple Access
An access mode approved for the radio interface of 3G(g)
or third generation Cellular Radio(g)
systems. It divides available radio spectrum into highly efficient
information carriers based on a special coding scheme. It is characterized
by high capacity, small cell radius and spread spectrum(g)
radio transmission. A technology for wideband digital radio communications
of Internet, multimedia, video and other capacity-demanding applications.
WCDMA, developed by InterDigital, Ericsson, Nokia and others, has
been selected for the third generation of mobile telephone systems
in Europe, Japan and the United States. The technology is also the
principal alternative being discussed in other parts of the world,
notably Asia. Also see Multiple Access(g);
Pilot Code(g);Spread Spectrum(g);
Synchronization(g). More see 3G standard,
a wireless ledger report.
WDM
Wave Division Multiplexing
Means of getting more information down a fiber optic cable by
using different wavelengths of light – i.e. different colors
within the light frequency spectrum – to act as multiple carriers.
Typical numbers of wavelengths being used are 4, 8 and 16, although
in the labs the laser has been split into 32 and even 100 channels.
Theoretically WDM could allow all US data traffic to be carried
on just one fiber optic pair.
WiFi Wireless Fidelity
A fixed, unlicensed spectrum technology known scientifically as
802.11b. The technology was originally developed to link PC's (personal
computers) in small, wireless clusters. WiFi is cuttingly used to
proved Internet to laptops and desk tops in homes out offices as
well as airports, hotel lobbies and coffee shops.
In 2002 there are grassroots' efforts to create Internet "clouds"
intended to eventually bypass the networks of big telecommunications
providers. Advocates say that while usage today is limited to several
hundred feet around the antenna, eventually the range could grow
to a dozen miles with a stronger antenna.
WiFi advocates claim that the technology could take away 10% to
20% of the market from 3G operators The UMTS (g)
forum (industry group) says there likely will be 20 million users
of public WLANS (WiFi) worldwide by 2005, generating about $2.8
billion. The UMTS forum believes the 3G market will be worth an
amazing $320 billion by 2010.
The 3G technology that competes directly with WiFi is wideband
TDD (WTDD) (g). WTDD beats WiFi with fall worldwide
mobility/roaming, security not available in unlicensed spectrum,
oval full intaration with other wireless and wired technologies.
InterDigital Communications Corp. (NASDAQ:IDCC) oval Siemens are
the worlds layers holders of the TDD (g) protocol
technology included in international standards for WCDMA (g)
and TD-SCDMA (g). 802.11b wireless Loud
Area Network (LAN) see W-LAN
Wideband
In wireless communications, wideband can handle full motion video
images or data transmission at megabit speeds
.WIPN
Wireless Internet packet-based network
Basically, the WIPN architecture consists of a packet-based core
network infrastructure optimized for an Internet Protocol applications
architecture. This involves an evolution to a common packet architecture
for voice and data traffic with distributed access, transport, routing/switching
and control functions.
Wireless
Radio-based systems that allow transmission of information without
a physical connection, opposed to transmission systems, that require
a physical connection, such as copper wire or optical fiber.
Wireless Access
Using radio communications to replace the access portion telecommunications
network. Wireless can provide either fixed (stationary) or mobile
access.
Wireless local loop
A form of wireless access that utilizes radio to connect fixed
end users to the PSTN(g) and provide
standard telephone services. See FWA(g).
WLAN
Wireless-Local Area Network
A wireless version of the LAN. Provides access to the LAN even
when the user is not in the office.
WP-CDMA
Wideband Packet Code Division Multiple Access.
Somewhere between Narrowband(g) and
Broadband(g). While capable of supporting
communications links of up to megabit speeds and therefore moving
images and very fast information downloads, this may be done at
the cost of overall bandwidth availability to other applications
and other users.
WTDD
Another name for braodband, Incorporating more then one channel
into a communications transmission contrast with Narrowband (g)
see WCDMA (g).
xDSL
x Digital Subscriber Line
Collective description for a range of Digital Subscriber Line
technologies designed to provide high speed data links over ordinary
copper telephone lines. Asynchronous DSL (ADSL), for example, is
called asynchronous because the downstream (to the customer) speed
is faster than the upstream (to the telco[g]) speed. ADSL speeds are typically 1.5 – 6 Mbps downstream
and 64 kbps upstream. Very high data rate DSL (VDSL) is similar
to ADSL, but operates at 12 – 51 Mbps downstream and 1.6 –
2.3 Mbps upstream. Rate Adaptive DSL (RADSL) is also similar to
ADSL but the transfer rate can be altered allowing it to work over
poorer quality lines or over longer distances, albeit at lower speeds.
High Bit Rate Digital Subscriber Line (HDSL) uses the same modulation
as ISDN(g) on a wider bandwidth and with more
sophisticated processing. It operates at speeds of up to 2 Mbps
at distances up to 4 km.
XML
Extensible Markup Language
New way of creating information content for the World Wide Web.
A complement to HTML(g), XML not only describes
the appearance of the elements of a web page but also the function.
XML should allow advanced interactive applications in banking, e-commerce
and many other areas to be created more easily and effectively,
and should dramatically improve web access times, especially for
business and home users.
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