Glossary of terms

BB

Broadband

Broadband is a wide bandwidth data transmission with an ability to simultaneously transport multiple signals and traffic types. The medium can be coaxial cable, optical fibre or radio.

BLER

Block Error Rate

A ratio of the number of erroneous blocks to the total number of blocks received on a digital circuit. Block error rate (BLER) is used for W-CDMA performance requirements tests (demodulation tests in multipath conditions, etc.).

BSC

Base Station Controller

BSC is a critical mobile network component that controls one or more base transceiver stations (BTS), also known as base stations or cell sites. Key BSC functions include radio network management, such as radio frequency control, BTS handover management and call setup.

BSS

Base Station System

BSS is the section of a traditional cellular telephone network which is responsible for handling traffic and signalling between a mobile phone and the network switching subsystem. The BSS carries out transcoding of speech channels, allocation of radio channels to mobile phones, paging, transmission and reception over the air interface and many other tasks related to the radio network.

BTS

Base Transceiver Station

BTS is equipment that facilitates wireless communication between user equipment (UE) and a network. UE are devices like mobile and smart phones, WLL phones and computers with wireless internet connectivity. The network can use any of the wireless communication technologies like GSM, CDMA, wireless local loop, Wi-Fi, WiMAX or other wide area network (WAN) technology.

CSR

Cell Site Router

The Extreme Networks E4G-200 Cell Site Router (CSR) is where 4G backhaul begins and where the T1/E1 pseudo wire circuit connection for 2G/3G is also initiated. Installation is either in or very near to the base station tower.

DAS

Distributed Antenna System

A distributed antenna system is a network of spatially separated antenna nodes connected to a common source via a transport medium that provides wireless service within a geographic area or structure. DAS antenna elevations are generally at or below the clutter level and node installations are compact.

DB

Distribution Board

A component of an electricity supply system that divides an electrical power feed into subsidiary circuits, while providing a protective fuse or circuit breaker for each circuit in a common enclosure. Normally, a main switch, and in recent boards, one or more residual-current devices (RCD) or residual current breakers with overcurrent protection (RCBO), are also incorporated

dB

Decibel

A logarithmic unit used to express the ratio of two values of a physical quantity, often power or intensity. One of these values is often a standard reference value, in which case the decibel is used to express the level of the other value relative to this reference. The number of decibels is ten times the logarithm to base 10 of the ratio of two power quantities, or of the ratio of the squares of two field amplitude quantities. One decibel is one tenth of one bel, named in honour of Alexander Graham Bell.

dBc

dB referenced to carrier

The power ratio of a signal to a carrier signal, expressed in decibels. For example, phase noise is expressed in dBc/Hz at a given frequency offset from the carrier. dBc can also be used as a measurement of Spurious-Free Dynamic Range (SFDR) between the desired signal and unwanted spurious outputs resulting from the use of signal converters such as a digital-to-analogue converter or a frequency mixer.

dBd

Antenna gain

A key performance number which combines the antenna's directivity and electrical efficiency. As a transmitting antenna, the gain describes how well the antenna converts input power into radio waves headed in a specified direction. As a receiving antenna, the gain describes how well the antenna converts radio waves arriving from a specified direction into electrical power. When no direction is specified, "gain" is understood to refer to the peak value of the gain. A graphic of the gain as a function of direction is called the radiation pattern.

dBi

dB referenced to isotropic radiator

A theoretical point source of electromagnetic or sound waves which radiates the same intensity of radiation in all directions. It has no preferred direction of radiation. It radiates uniformly in all directions over a sphere centred on the source. Isotropic radiators are used as reference radiators with which other sources are compared.

dBm

dB referenced to one milliwatt

An abbreviation for the power ratio in decibels (dB) of the measured power referenced to one milliwatt (mW). It is used in radio, microwave and fibre optic networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form. In comparison, dBW refers to one watt (1000 mW).

Ec/Io vs. Ec/No

Energy measurement before versus after dispreading

Io = own cell interference + surrounding cell interference + noise density
No = surrounding cell interference + noise density
That means, ‘Io’ is the total received power density including the CPICH of its own cell. ‘No’ is the total received power density excluding the CPICH of its own cell.  Technically Ec/Io should be the correct measurement but, due to equipment characteristics, Ec/No is actually measured.  In UMTS, Ec/No and Ec/Io are often used interchangeably.

ETSI

European Telecommunications Standards Institute

An independent, not-for-profit, standardisation organisation in the telecommunications industry (equipment makers and network operators) in Europe, headquartered in Sophia-Antipolis, France, with worldwide projection. The ETSI produces globally-applicable standards for Information and Communications Technologies (ICT), including fixed, mobile, radio, converged, broadcast and internet technologies.

FDD

Frequency Division Duplexing

A technique where separate frequency bands are used at the transmitter and receiver side. Because the FDD technique uses different frequency bands for send and receive operations, the sending and receiving data signals don't interfere with each other. This makes FDD a better choice than Time Division Duplex (TDD) for symmetric traffic such as voice applications in broadband wireless networks.

GPRS

General Packet Radio Service

A packet oriented mobile data service on the 2G and 3G cellular communication system's global system for mobile communications (GSM)

HLR

Home Location Register

The main database of permanent subscriber information for a mobile network. The HLR is an integral component of CDMA (code division multiple access), TDMA (time division multiple access), and GSM (Global System for Mobile communications) networks.

IDC

Insulation Displacement Connector

Also known as insulation-piercing contact (IPC). It is an electrical connector designed to be connected to the conductor(s) of an insulated cable by a connection process which forces a selectively sharpened blade or blades through the insulation, bypassing the need to strip the conductors of insulation before connecting. When properly made, the connector blade cold-welds to the conductor, making a theoretically gas-tight reliable connection.

idDAS

Intelligent Digital DAS

An adaptable, customisable and expandable cellular and data coverage solution for multiple operators and services over a common infrastructure.

IDF

Insulation Displacement Frame

Combines various IDC’s in the same housing on a common frame.

IPNet

IP Network

Is a communication network that uses Internet Protocol (IP) to send and receive messages between one or more computer/s. As one of the most commonly used global networks, an IP network is implemented in Internet networks, local area networks (LAN) and enterprise networks.

LTE

Long Term Evolution

Refers to a standard for smooth and efficient transition toward more advanced leading-edge technologies to increase the capacity and speed of wireless data networks. LTE is often used to refer to wireless broadband or mobile network technologies. LTE is also referred to as 3GPP Long Term Evolution. 3GPP is an acronym for 3rd Generation Partnership Project, which operates under a name trademarked by the European Telecommunications Standards Institute. LTE is also known as LTE Super 3G and LTE Super 4G.

LSW

LAN Switch

A network device that cross-connects clients, servers and network devices. Also known as a "frame switch". Stand-alone LAN switches are common in ethernet networks. A four-port switch is also typically built into a wired or wireless router for homes and small business (see wireless router)

ME

Metro Ethernet

The use of carrier ethernet technology in metropolitan area networks (MANs). Because it is typically a collective endeavour with numerous financial contributors, Metro Ethernet (ME) offers cost-effectiveness, reliability, scalability and bandwidth management superior to most proprietary networks.

MTTR

Mean Time to Repair

A basic measure of the maintainability of repairable items. It represents the average time required to repair a failed component or device. Expressed mathematically, it is the total corrective maintenance time for failures divided by the total number of corrective maintenance actions for failures during a given period of time. It generally does not include lead time for parts not readily available or other Administrative or Logistic Downtime (ALDT).

MIMO

Multi-In, Multi-Out

In radio, multiple-input and multiple-output, or MIMO (pronounced as ‘my-moh’ or ‘me-moh’), is a method for multiplying the capacity of a radio link using multiple transmit and receive antennas to exploit multipath propagation.

NE

Network Element

A manageable logical entity uniting one or more physical devices. This allows distributed devices to be managed in a unified way using one management system. According to the Telecommunications Act of 1996, the term 'network element' means a facility or piece of equipment used in the provisioning of a telecommunications service. The term also includes features, functions, and capabilities that are provided by means of such facility or equipment, including subscriber numbers, databases, signalling systems, and information sufficient for billing and collection used in the transmission, routing, or other provisions of a telecommunications service.

PIM

Passive Intermodulation

PIM is a growing issue for cellular network operators. PIM issues may occur as existing equipment ages, when co-locating new carriers or when installing new equipment. PIM is a particular issue when overlaying (diplexing) new carriers onto old antenna runs. PIM can create interference that will reduce a cell’s receive sensitivity or even block calls. This interference can affect both the cell that creates it, as well as other nearby receivers. PIM is created by high transmitter power. Therefore on-site PIM testing needs to be done at or above the original transmitter power levels to detect any PIM issues.

RF

Radio Frequency

Any of the electromagnetic wave frequencies that lie in the range extending from around 3 kHz to 300 GHz. These include frequencies used for communications or radar signals. RF usually refers to electrical rather than mechanical oscillations. However, mechanical RF systems do exist. Although radio frequency is a rate of oscillation, the term "radio frequency" or its abbreviation "RF" are used as a synonym for radio – i.e., to describe the use of wireless communication, as opposed to communication via electric wires.

RAN

Radio Access Network

Part of a mobile telecommunication system. It implements a radio access technology. Conceptually, it resides between devices such as a mobile phone, computer, or any remotely controlled machine and provides connection with its core network (CN).

RNC

Radio Network Controller

A governing element in the UMTS radio access network (UTRAN), which is responsible for controlling the connected secondary nodes.

RRU

Remote Radio Unit

The RRU and the controller form the Base Transceiver Station (BTS), which is commonly used in cellular communication.

RSSI

Received Signal Strength Indicator

A Radio Frequency (RF) term which refers to the power level measurement that a RF device, such as WiFi or 3G client, is receiving from the radio infrastructure at a given location and time.

RSCP

Received Signal Code Power

In the UMTS cellular communication system, RSCP denotes the power measured by a receiver on a particular physical communication channel. It is used as an indication of signal strength, as a handover criterion, in downlink power controls and to calculate path loss.

RSRP

Reference Signal Received Power

A combination of various parameters such as RSSI, RSRQ and RSTD. RSRP is the average power received by UE from a single cell specific reference signal resource element spread over the full bandwidth.

RSRQ

Reference Signal Received Quality

RSRQ = N x RSRP / RSSI. N is the number of Physical Resource Blocks (PRBs) over which the RSSI is measured, typically equal to system bandwidth.

SAM

Site Asset Management Unit

A control unit used on BTS sites.

SDH

Synchronous Digital Hierarchy

A standard technology for synchronous data transmission on optical media. The technology provides faster and less expensive network interconnection than traditional PDH (Plesiochronous Digital Hierarchy) equipment.

SISO

Single In , Single Out

A simple single variable control system with one input and one output. In radio networks it utilises only one antenna for transmitting and receiving.

SNR or S/N

Signal-to-Noise Ratio

A measurement used to compare the level of a desired signal to the level of background noise. It is defined as the ratio of signal power to the noise power and often expressed in decibels.

SON

Self-Organising Network

An automation technology designed to make the planning, configuration, management, optimisation and healing of mobile radio access networks simpler and faster. SON functionality and behaviour has been defined and specified in generally accepted mobile industry recommendations produced by organisations such as 3GPP (3rd Generation Partnership Project) and the NGMN (Next Generation Mobile Networks).

SIR or S/I		Signal-to-Interference Ratio
CIR or C/I		Carrier-to-Interference Ratio

The quotient between the average received modulated carrier power S or C and the average received co-channel interference power I. It measures cross-talk from other transmitters compared to the useful signal.

TEMS

Transport Element Management System

Consists of systems and applications for managing network elements on the network element-management layer of the Telecommunications Management Network model.  The element management system's key functionality is divided into five key areas including fault, configuration, accounting, performance and security.

TDD

Time Division Duplexing

Refers to duplex communication links where the uplink is separated from the downlink by the allocation of different time slots in the same frequency band. It is a transmission scheme that allows asymmetric flow for uplink and downlink data transmission.

UARFCN

UTRA Absolute Radio Frequency Channel Number

UTRA stands for UMTS Terrestrial Radio Access and is used to identify a frequency in the UMTS frequency bands.

UMTS

Universal Mobile Telecommunications System

A third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunications Union IMT-2000 standard set and compares with the CDMA 2000 standard set for networks based on the competing CDMA-One technology. UMTS uses wideband code division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators.

VoLTE

Voice over LTE

Based on the IP Multimedia Subsystem (IMS) network, with specific profiles for control and media planes of voice services on LTE defined by GSMA in PRD IR.92. This approach results in the voice service (control and media planes) being delivered as data flows within the LTE data bearer. This means that there is no dependency on (or ultimately, requirement for) the legacy circuit-switched voice network to be maintained. VoLTE has up to three times more voice and data capacity than 3G UMTS and up to six times more than 2G GSM. Furthermore, it frees up bandwidth because VoLTE’s packet headers are smaller than those of un-optimised VoIP/LTE.

VLR

Visitor Location Register

A database of the subscribers who have roamed into the jurisdiction of the MSC (Mobile Switching Centre). Each main base station in the network is served by only one VLR (one BTS may be served by many MSCs in case of MSC in pool. Therefore a subscriber cannot be present in more than one VLR at a time.

VSWR

Voltage Standing Wave Ratio

A measurement of imperfections in a transmission line or waveguide. SWR is defined as the ratio of the partial standing wave's amplitude at an antinode (maximum) to the amplitude at a node (minimum) along the line.