RFComprehensive Glossary of RF and Wireless Terms
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This glossary covers terms related to RF (Radio Frequency), wireless communication, Digital Signal Processing (DSP), and data communication. It’s designed to be helpful for both beginners and experts in the RF and wireless fields.
A
Access Point (AP): A network device or communication hub that connects wireless devices (stations) to a Wireless Local Area Network (WLAN). It provides access to Wi-Fi network resources for stations requesting to join.
AES (Advanced Encryption Standard): A widely used encryption standard for providing security to data, voice, and other services. AES supports key lengths from 128 to 256 bits.
Air Interface: The medium between a Base Station (BS) and subscribers (or wireless devices like tablets and mobile phones) used for RF frequency communication, or the medium between a wireless Access Point and stations.
Analog: In telecommunications, an early wireless network technology that modulates radio signals to transmit information as sound waves. It allows one call per channel.
ANSI (American National Standards Institute): A non-governmental organization that develops and publishes standards for transmission codes and protocols in the United States.
API (Application Programming Interface): A set of standard methods or functions that application programs use to access services or tools, such as network services and program-to-program commands.
Asynchronous Communication: Communication signals that don’t rely on a shared timing mechanism for transmitting and receiving information.
Attenuation: A loss of signal strength as it travels through a medium, usually measured in decibels (dB).
AWGN (Additive White Gaussian Noise): Additive noise present in a signal due to thermal noise and other atmospheric noises. It has a Gaussian distribution with a mean of 0 and variance of 1.
B
Backhaul: The systems that connect wireless network connectivity to the internet (or Packet Data Network) to provide voice and data services to users.
Band: In wireless communications, a frequency or continuous range of frequencies.
Bandwidth: The range of frequencies. Analog bandwidth is measured in hertz (Hz), while digital bandwidth is the volume of data a channel can carry, measured in bits per second (bps).
Base Station: A cell tower or cell site, a transmitter/receiver location that establishes radio links between subscribers or wireless devices. It includes an antenna tower, transmission radios, and radio controllers. Each geographic area in a cellular network requires a base station.
Baseband Signal: An unmodulated signal, typically with a frequency range around 0 Hz. Complex signals before DAC/frequency conversion are considered baseband signals.
Beacon: A type of packet broadcast by access points or stations to keep the network synchronized. In satellite communication, a beacon carrier is a reserved carrier used for antenna alignment on Earth.
BER (Bit Error Rate): A measure of the quality of a telecommunication link, calculated as the ratio of bits in error to the total bits transmitted.
Bit Rate: The speed at which data is transmitted over a medium, usually measured in bits per second.
BPSK (Binary Phase Shift Keying): A digital modulation technique where two phases of the carrier frequency represent digital data (1 and 0) using 180-degree and 0-degree phases, respectively. One bit is represented by the carrier in each time period.
Bluetooth: A short-range wireless technology for interconnecting devices like phones, computers, keyboards, microphones, and mice. It supports both voice and data communications.
BPS (Bits Per Second): A standard for measuring the smallest unit of information in digital communications and data processing applications.
Broadband: A generic term for high-speed digital internet connections, such as wireline, DSL, cable modems, and wireless third-generation technologies.
BSID (Base Station Identifier): The unique number assigned to a Base Station for identification in wireless networks.
BSC (Base Station Controller): A component of a base station subsystem that supervises the functioning and control of multiple BTSs.
BTS (Base Transceiver Station): Includes the transmitter, receiver, and antenna systems. It interacts with cellular phones and internet devices in the wireless network.
C
C Programming: A programming language mainly used for embedded applications requiring more interaction with hardware.
Carrier: In wireless communications, an electromagnetic pulse or radio wave transmitted at a stable base frequency, usually a higher radio frequency. It’s used to transmit baseband signals over long distances using an antenna.
CCDF (Complementary Cumulative Distribution Function): A measure of variation in the power of a baseband signal at the baseband transmitter. It plots relative power levels versus probability, determining the specifications of the Power Amplifier (PA) needed in the transmitter.
CCITT (Consultant Committee on International Telephone and Telegraph): An international organization that develops standards and defines interfaces for telecommunications.
CCK (Complementary Code Keying): A modulation scheme that transforms data blocks into complex codes, encoding several bits per block. Mainly used in 802.11b Physical layer for 5.5 and 11 Mbps rates.
Convolution Codes: A class of codes that can detect and correct errors, used in wireless systems like WLAN, WiMAX, LTE, and satellite communications. They add redundancy to data for power efficiency.
CRC (Cyclic Redundancy Check): A checksum on integers (modulo-2 Sum), a common error detection (not correction) protocol used in data communication, found in almost all MAC layers.
CTS (Clear to Send): A signal from the receiving station to the transmitting station granting permission to transmit data, used in 802.11agn. A station responds to an RTS (Request to Send) with a CTS frame.
CDG (CDMA Development Group): An international consortium of companies leading the adoption and evolution of CDMA-based wireless systems.
CDMA (Code Division Multiple Access): A digital wireless technology that converts analog information into digital information, then transmits it as a radio signal over a wireless network. CDMA uses spread-spectrum technology, spreading information over a larger band for security. Walsh codes are used for this purpose.
Cell: The geographical area served by one Base Station, based on signal power level sufficient for a reliable connection to subscribers.
Cellular: Analog or digital communications that provide a consumer with a wireless connection from a mobile device to a Base Station.
Channel: The amount of wireless spectrum occupied by users or end devices, similar to bandwidth.
Circuit-Switched Network: Networks that establish a temporary physical circuit “connection” and keep it reserved for the user until a disconnect signal is received. A dial-up modem is an example.
Cyclic Prefix: A portion of each OFDM symbol extracted from the end and appended at the beginning to combat multi-path delay spread in mobile communication channels. It’s kept greater than the channel’s delay spread.
D
DAC (Digital to Analog Converter): An electronic device or software that converts a digital number or signal into a corresponding analog voltage or current.
DAMA (Demand Assigned Multiple Access): A technique for sharing satellite bandwidth among many users based on demand, making bandwidth use more efficient.
Decibel (dB): A unit for expressing a logarithmic measure of the ratio of two signal levels, commonly used for power, voltage, and current ratios:
Decoder: Hardware or software that decodes encoded data into its original format.
Demodulator (De-mapper): Hardware or software that demodulates modulated data back to raw bit format.
Digital: A form of transmission that transforms analog signals into a series of electrical or optical pulses representing binary digits 0 and 1.
DSP (Digital Signal Processing): A technique used for speech and data processing in advanced wireless communication systems.
DOT (Department of Telecommunications): The India Government body overseeing policy, licensing, and coordination of telegraphs, telephones, wireless, data, facsimile, and telemetric communications.
Downlink: The connection from the network to the end-user communication device. In satellite communications, it refers to the connection from a satellite to a terrestrial receiver or VSAT or ground station. In wireless communications, it’s the connection from the Base Station to the subscriber station, also known as the Forward link.
Dual Mode: Functionality that allows a mobile phone to operate in two different modes for greater roaming capabilities, such as supporting both CDMA2000 and WCDMA standards.
E
EDGE (Enhanced Data Rates for Global Evolution): A software/hardware enhancement for GSM networks to provide higher data rates for multimedia and broadband applications.
Embedded: In wireless communications, describes capabilities like internet access housed in a device.
Ethernet: A network protocol evolved through iterations to support higher speeds, defined for various physical media like copper, multi-mode fiber, and single-mode fiber.
Encoder: Hardware or software that encodes data, accepting message bits and adding redundancy according to a rule.
Equalization: The process of shaping received pulses to compensate for amplitude and phase distortions caused by channel imperfections, mainly used in channel equalization techniques.
EVM (Error Vector Magnitude): A measure of the performance of a digital radio transmitter or receiver, quantifying how far constellation points are from ideal locations.
eNodeB: The base transceiver station (BTS) in LTE technology, also termed eNB.
F
FCC (Federal Communications Commission): The U.S. government agency responsible for regulating the communications industry.
Fading: The variation in a received signal’s amplitude due to interference.
FHSS (Frequency Hopping Spread Spectrum): A technique used in radio transmission systems, like WLANs and mobile networks, that converts a data stream into packets sent in short bursts via transmitters and receivers that “hop” from one frequency to another. The hopping sequence is known at both ends, mainly used for security.
Firewall: A combination of hardware and software that protects a computer or network from attacks.
Frequency: The rate at which an electromagnetic waveform alternates, measured in hertz (Hz) or megahertz (MHz).
Frequency Offset: The difference between the ideal frequency and measured frequency.
Forward Error Correction (FEC): A technique used in wireless communication to make the system power-efficient by correcting errors at both bit and block levels, such as with convolutional encoders and Reed-Solomon encoders.
G
Gateway: A network point that acts as an entrance to another network, interfacing between heterogeneous networks.
GB (Gigabyte): A measure of computer data storage capacity, approximately one billion bytes.
GHz (Gigahertz): A measure of frequency equal to one billion hertz or one thousand megahertz (MHz).
GPRS (General Packet Radio Service): A packet-linked technology that enables wireless internet and other data communications, providing faster speeds than GSM systems.
GPS (Global Positioning System): A worldwide radio-navigation system that enables users to determine their exact location using radio signals from orbiting satellites.
GSM (Global System for Mobile Communications): A leading digital cellular system using narrowband TDMA (Time Division Multiple Access). Eight simultaneous calls can occupy the same radio frequency, with each frequency band used by eight time slots.
H
Handoff: The process of transferring a cellular phone conversation from one base station to another without interruption, happening at various levels in a wireless network.
Handset: A wireless device with a transmitter and receiver, also known as a cell phone or mobile phone.
Hard Handoff: A handoff that requires breaking the connection of a cellular phone call in the original base station before connecting to the next, potentially resulting in dropped calls.
Hertz: The international unit for measuring frequency, with one megahertz (MHz) equaling one million Hertz, and one gigahertz (GHz) equaling one billion hertz.
HSDPA (High-Speed Downlink Packet Access): Specified in 3GPP Release 5, extending WCDMA with transport and control channels like the high-speed downlink shared channel (HS-DSCH).
HSUPA (High-Speed Uplink Packet Access): An enhancement to WCDMA networks that provides higher data speeds in the uplink for applications like VPN access and large file transfers.
I
IEEE (Institute of Electrical and Electronics Engineers): A standards body responsible for developing computing and electronics standards, including 802.11 and 802.16 for WLANs and WiMAX.
IEEE 802.11: WLAN technologies that complement access technologies for broadband networks.
IETF (Internet Engineering Task Force): The body that defines standard Internet operating protocols like TCP/IP.
IP (Intellectual Property): A proprietary design that companies license to prevent others from copying.
IM (Instant Messaging): Real-time, text-based communication between two or more people over a network like the internet.
IQ Signal: Abbreviated for “in-phase and quadrature-phase of the signal,” fundamental products of individual in-phase and quadrature modulators that are exactly 90 degrees out of phase.
Interoperability: The ability of heterogeneous systems and networks to communicate and co-operate through specified standards.
Internet Protocol (IP): Specifies the format and address scheme of information packets sent over the internet, allowing you to label a package with the destination address. When combined with protocols like TCP, a virtual connection is established.
ISDN (Integrated Services Digital Network): A set of standard specifications for access technologies and services built on traditional PSTN networks for enhanced and integrated voice and data communication.
ISO (International Organization for Standardization):
IT (Information Technology):
ITU (International Telecommunications Union): An agency of the United Nations with the goal of establishing telecommunication standards.
J
Java: A programming language developed by Sun Microsystems for creating and running software programs on a single computer and in networked environments. Java programs are portable and can be run anywhere in a network that has a Java virtual machine (JVM).
JPEG: A standard file format for image compression, typically for photographic images. Commonly used to store and transmit photographs over the Internet. The most common file extensions for this format are .jpg or .jpeg.
JVM (Java Virtual Machine): Interprets compiled Java code for a computer’s processor so it can execute a Java program’s instructions.
Jamming: Intentionally transmitting signals in a particular frequency band to disrupt reception of signals.
K
KB (Kilobyte): A measure of computer memory or storage, measured as 1,024 bytes in decimal notation.
Kbps (Kilobits per second): Commonly used as a speed for data transmission. Measured as 1,000 bits per second.
Kilohertz (KHz): One thousand hertz. A measurement often used to reference radio frequencies.
L
LABVIEW: A programming language mainly used for data acquisition and Graphical User Interface, developed by National Instruments.
LAN (Local Area Network): A small communication network covering a limited area, such as within a building or group of buildings.
Last Mile: Commonly used in telecommunications for the final delivery of communications connectivity between the network and the end user’s point of access (home or business).
Line of Sight: In line of sight transmission the transmitting and receiving stations (antennas) can see each other. It’s a clear path between transmitting and receiving stations.
LTE (Long Term Evolution): A standard for wireless communication of high-speed data for mobile phones and data terminals. The standard is developed by the 3GPP (3rd Generation Partnership Project). It is also called as 4G and is the future mobile broadband cellular system.
M
MATLAB: A high-level language and interactive environment that enables you to perform computationally intensive tasks faster than with traditional programming languages.
MAC (Medium Access Control): A protocol used for controlling and accessing physical medium. In OSI model it is lower layer prior to PHY layer. The primary functions of the MAC layer is to control and access the physical medium, and also performs fragmentation and de fragmentation of packets. It also takes care of scheduling and priority handling.
Microwave: The electromagnetic waves of very high frequency mainly used in wireless communication.
MB (Megabyte): A measure of computer processor storage and real and virtual memory. Measured as 1,048,576 bytes in decimal notation.
Mbps (Megabits per second): Measured as one million bits per second. A measurement of the amount of data transferred in one second between two telecommunication points.
MHz (Megahertz): One million hertz or cycles per second. A measurement often used to describe the speed of digital and analog signals.
MIMO (Multiple Input, Multiple Output): In wireless communications, an antenna technology that uses multiple antennas at the source (transmitter) and the destination (receiver). This will increase the data rate/robustness based on the technique employed at the transmitter.
Modulator (Mapper): It is the technique which will change amplitude, frequency or phase of carrier wave in accordance with the modulating or baseband signal.
MSC (Mobile Switching Center): A sophisticated telephone exchange that provides mobility management services, such as circuit-switched calling, and coordination between base stations (cell towers), networks and mobile users within a network.
Multicast: Simultaneous transmission of content from a single source to large numbers of wireless subscribers. Usually refers to the delivery of a wide variety of TV-like programming to wireless devices.
Multipath: The multiple paths a radio wave may follow between transmitter and receiver. In cellular communications, refers to a radio signal reaching the receiving antenna by two or more paths.
Multipath Fading: Interference during wireless signal reception caused by the deflection of a radio signal off obstacles such as buildings, mountains and other large obstructions.
Multiplexing: Multiplexing is a technique where multiple channels are combined for transmission over a single transmission path. Mainly TDM and FDM is used.
N
Node: A point of connection into a network. In packet-switched networks, a node is one of the many packet switches that form the network’s backbone.
Node B: Denotes the base transceiver station (BTS) in WCDMA technology.
Noise: Unwanted signal superimposed on a true signal.
O
OEM (Original Equipment Manufacturer): The manufacture of a device (often a consumer electronics product).
OFDM (Orthogonal Frequency Division Multiplexing): A wireless communications technology and modulation technique that divides available spectrum into multiple radio frequency (RF) channels. IEEE standards 802.11a, 802.16 use this technique for transmission of data. This allocates resources to the users in time plane.
OFDMA (Orthogonal Frequency Division Multiple Access): This allocates resources to the users both in time and frequency grid.
Operating System (OS): Software that manages the basic operations of a computer system. Examples include UNIX, Windows, Palm OS and Mac OS X.
Operator: A wireless network operator, also often referred to as a carrier or service provider, which provides mobile telecommunication services.
OSI (Open Systems Interconnection): A reference model established by the ISO to provide a network design framework that allows equipment from different vendors to be able to communicate using set of protocols.
P
Packet: A digital “package” of data that enables efficient use of radio spectrum and routing over a network, such as the Internet or wireless networks. Each packet is numbered separately and includes the Internet address of the destination.
Packet-Switched Network: Networks that transfer digital packets of data. Packet-switched networks are connectionless or “always on,” eliminating the need to connect to a network to send or receive data. In contrast, circuit-switched networks require a dedicated circuit, or connection, for the duration of the data transmission.
PCMCIA (Personal Computer Memory Card International Association): An international association that standardizes credit-card sized wireless modems which can be inserted into laptops or other mobile computing devices to connect to the Internet. A Type II PC card is the most common PCMCIA card.
PER (Packet error rate): Packet error rate (PER) is an average fraction of transmitted packets that are not detected correctly.
Phase Offset: Difference in reference phase of transmitted waveform and received waveform is called phase offset, expressed in degree.
PCS (Personal Communications Services): Refers to the 1900 MHz cellular frequency band. More commonly used as a marketing term to describe digital wireless services in the Americas, regardless of the particular frequency band being used.
PDA (Personal Digital Assistant): A portable personal computing device used for text messaging, email, calendar, contacts and a wide range of other applications.
PHY (Physical Layer): Transmits raw bits of data by establishing and terminating connections to a networked communications resource. Refers to network hardware, physical cabling or a wireless connection. Considered layer one of the seven-layer OSI (Open Systems Interconnection) model of data communications.
Pilot: A single frequency signal which is transmitted for synchronization or reference purposes.
Preamble: A predefined pattern known both at Transmitter and Receiver used for synchronization purpose, mainly for time, frequency synchronization and channel estimation-equalization.
Project: A project is a temporary endeavor undertaken to create a unique product, service, or result.
Program: A program is defined as a group of related projects managed in a coordinated way to obtain benefits and control not available from managing them individually.
PPP (Point-to-Point Protocol): A protocol for communication that allows two devices to transport packets over a data connection, such as a personal computer connected by phone line to a server.
Protocol: Within the context of data communications, a specific set of rules related to data transmission between two devices. Protocols set standard procedures that enable different types of data devices to recognize and communicate with each other.
PSTN (Public Switched Telephone Network): Refers to the local, long-distance and international phone system. In the United States, PSTN refers to the entire collection of interconnected phone companies.
Q
QAM (Quadrature Amplitude Modulation): Where carrier signal’s amplitude as well as phase is varied in accordance to the information bits. In the case of 16QAM, 4 bits represented by one carrier.
QoS (Quality of Service): A measure of network’s transmission reliability and efficiency. QoS is commonly used by network operators to indicate a higher level of service guarantee to customers.
QPSK (Quadrature Phase Shift keying): A modulation method that encodes two bits as each carrier phase shift.
R
Randomization: A technique used in digital baseband chain used to remove long string of 1’s. Basic randomization circuit is Ex-OR gate.
Receiver sensitivity: Ability of the receiver to work satisfactorily to the minimum of power level.
Reverse Link (Uplink): The connection from the end-user communications device to the network. In satellite communications, also refers to the connection from a terrestrial transmitter (ground Station) to a satellite. In wireless communication it refers connection from Subscriber to the BS.
RF (Radio Frequency): Measured in Hertz, MHz and GHz. Wireless and cordless telephones, radio and television broadcast stations, satellite communications systems and two-way radio services all operate using radio frequencies.
RFID (Radio Frequency Identification): A method of remotely retrieving data from and storing data associated with animals, people, products or equipment. Requires an RFID tag which contains an antenna to enable the tag to send and receive queries from an RFID transceiver.
RJ-11: Standard 4-wire connectors for phone lines.
RJ-22: Standard 4-wire connectors for phone lines with secondary phone functions (such as call forward, voice mail, or dual lines).
RJ-45: Standard 8-wire connectors for networks. Also used as phone lines in some cases.
RNA (Remote Network Access): Terminology being used for the hardware/software for connecting remote workers, offices, customers and suppliers through non-dedicated (dial-up/ISDN) connections.
Roaming: The ability to access a network anywhere and move freely while maintaining an active link through a wireless connection to a network. Roaming usually requires a handoff when a node (user) moves from one cell to another.
Router: A device that interconnects two dissimilar networks. For example, it connects LAN with WAN.
RNC (Radio Network Controller): Equipment in third-generation (3G) wireless networks that interfaces with the core network, controls the radio transmitters and receivers in Node Bs, and performs mobility functions.
ROI (Return On Investment): A financial performance measure to determine the relative attractiveness of a proposed investment. ROI is typically measured in dollars but can also be measured by less quantifiable benefits such as increased customer satisfaction.
S
SDK (Software Development Kit): A set of software tools, usually designed for use with a particular operating system, that enables software developers to write programs that will work on the target operating system.
Service Provider: A “carrier” or “network operator” that provides mobile telecommunication services.
SIMULINK: A programming language which provides interactive graphical environment along with the built in library for multi domain simulation.
Soft Handoff: The process, invisible to the user, of transferring a cellular phone conversation from one base station (cell tower) to another without interruption to the call. Soft handoffs do not require the original connection to be broken when transferring to an adjacent base station.
Spread Spectrum: A method of transmitting a radio frequency (RF) signal by “spreading” it over a broad range of frequencies. This facilitates reduced interference and increased capacity within a particular radio frequency band. CDMA technology is based on spread spectrum.
SS7 (Signaling System 7): The protocol used in public-switched telephone systems for establishing calls and providing services such as 800 numbers, call forwarding, caller ID and number portability.
Subscriber: In wireless, a user of a mobile telecommunication service.
Synchronous Communication: Transmissions that are timed by a clocking signal and occur with equal time intervals between them. An example is the constant transmission of time-sensitive data, such as real-time voice.
Sampling rate: Rate at which analog signal is sampled for digital conversion and vice versa.
T
TCP/IP (Transmission Control Protocol/Internet Protocol): A communications protocol that has become the de facto standard protocol for the Internet. “TCP” provides transport functions, ensuring that the total amount of data sent is correctly received. “IP” provides the routing mechanism, ensuring the information reaches the correct destination.
TDD (Time Division Duplexing): The application of time-division multiple access (TDMA) to separate inbound and outbound signals. Allows devices to transmit and receive on a single frequency at different time intervals.
TDMA (Time Division Multiple Access): A second-generation, digital wireless communication technology that increases the amount of data that can be delivered by dividing each cellular channel into time slots. Wireless standards that use TDMA technology include GSM, PDC and iDEN.
Thermal noise: Noise introduced in a communication system due to movement of electrons.
Turnaround time: The time required to transmit a message and receive its acknowledgement.
U
UMTS (Universal Mobile Telecommunications System): A third-generation (3G), CDMA-based wireless communication standard that offers enhanced voice and data capacity and higher data rates than previous, second generation wireless technologies.
Unicast: The transmission of content from a single source to a single receiver over a network.
Uplink: The connection from the end-user communications device to the network. In satellite communications, also refers to the connection from a terrestrial transmitter to a satellite. In wireless communication it is connection from Subscriber to BS.
V
VSAT (Very-Small-Aperture Terminal):
Viterbi decoder: Viterbi decoder is FEC (Forward error correction) Device, which will decode the convolution encoded data, and correct random single bit errors.
W
WAN (Wide Area Network): A geographically dispersed telecommunications network. A WAN may be privately owned or rented, but the term usually refers to a public network.
WCDMA: CDMA is a wideband spread-spectrum 3G mobile telecommunication air interface that utilizes code division multiple access (or CDMA the general multiplexing scheme, not to be confused with CDMA the standard). It provides simultaneous support for a wide range of services with different characteristics on a common 5MHz carrier
WEP (Wired Equivalency Privacy): An optional feature for Wi-Fi and 802.11b that offers privacy by using an encryption algorithm that scrambles data before any data is transmitted.
Wi-Fi: Short for “Wireless Fidelity” and another name for WLAN (wireless local area network). Allows a mobile user to connect to a local area network (LAN) through a wireless connection. Wi-Fi has been deployed in airports, universities, bookstores, coffee shops, office campuses and private residences.
WiMAX (Wireless Interoperability for Microwave Access): A group of proposed wireless standards for high-throughput broadband connections over long distances. Applications include “last mile” broadband connections and hot spots. Trade name for a new family of IEEE 802.16 wireless standards.
Wireless MAN (Metropolitan Area Network): Enables broadband network access with exterior antennas that communicate with base stations that are connected to core network. An alternative to fixed-line networks. Developed by the IEEE 802.16 Working Group.
WLAN (Wireless Local Area Network): Where the movement is within a contained geographical area, you can provide mobility by implementing a wireless LAN and equipping your mobile device with a corresponding wireless adapter - a PC card variety that goes into a notebook, hand-held PDA, a Windows CE-compatible device or Palm Pilot organizer. Allows a mobile user to connect to a local area network (LAN) through a wireless connection. WLANs have been deployed in airports, universities, bookstores, coffee shops, office campuses and private residences.
WPAN (Wireless Personal Area Network): These are wireless networks that can be installed in a small office or home within 5-15 metre distances. Two technologies being used for this purpose are IrDA which is based on line of sight requirement within two devices, usually a few feet apart. For more details on IrDA, please go to IrDA site. The second technology is Blue Tooth. Blue tooth technology supports multipoint connection without line of sight requirement.
X
XML (extensible Markup Language): A computer language developed by the World Wide Web Consortium (W3C) designed to improve the functionality of the Internet by providing a more flexible way to share basic data, such as phone numbers or addresses. For example, XML may be used to share data between desktop computers and wireless devices.
Z
ZIF (Zero Intermediate Frequency): A radio frequency architecture that eliminates the entire intermediate frequency section of the cellular phone, resulting in smaller-sized wireless devices. The basis of QUALCOMM’s radioOne technology.
