E.164. A public network addressing standard utilizing up to a maximum of 15 digits. ATM uses E.164 addressing for public network addressing.

E-AMPS (Extended AMPS). E-AMPS is an extended form of the AMPS system in which the number of available radio channels has been increased to 1023 through an increased spectrum allocation.

Earth station. A satellite communications device located on the Earth's surface.

Echo cancellation. A technique used in analog systems that isolates and filters interference from voice circuits.

Echo canceller. A device that removes interference from a speech channel. Echo cancellers cannot be used with some types of high speed modem calls and ISDN.

Echo suppressor. A device that attenuates the transmission path in the opposite direction to the transmitted signal in order to prevent reflected energy being echoed back to the signal transmitter.

ECM (Entitlement Control Message). A Conditional Access message that contains the key for decrypting transmitted programs. It is transmitted with the Entitlement Management Message.

ECMA International or (European Computer Manufacturers Association). ECMA International is an industry association founded in 1961 and dedicated to the standardization of information and communication systems. Before 1994 it was known as ECMA - European Computer Manufacturers Association.

EDGE (Enhanced Data rates for Global Evolution). A 3G wireless technology that triples the data capacity of GPRS.

EIA (Electronics Industries Association). The EIA is a national trade association, developing electrical standards primarily for North America.

EIA/TIA (Electronics Industries Association and Telecommunications Industries Association). An organisation in the United States consisting of two merged associations - the EIA and the TIA. The EIA is concerned with the specification of standards for hardware interfaces.

EIR (Equipment Identity Register). A database containing a list of all valid IMEIs on the network.

Each IMEI is given a colour code that indicates its status.

1. A white-listed IMEI means that the terminal is allowed to connect to the network.
2. A grey-listed IMEI indicates that the network is currently watching the terminal for possible problems.
3. A black-listed IMEI means that the terminal is not allowed to connect to the network, because it has either been reported stolen or is the wrong type of terminal for that particular GSM network.

EIRP (Effective Isotropic Radiated Power). The power radiated from an antenna, relative to an isotropic. It is measured in dBs or dBi's and represents the power supplied to an antenna plus its gain.

EIT (Event Information Table). A DVB SI table that contains data about what TV events are in the Transport Stream.

Electromagnetic spectrum. The complete range of wavelengths of electromagnetic radiation available.

Elevation. The angle of a satellite above the horizon.

E-mail Electronic mail. The transmission and reception of computer-stored messages by telecommunication. E-mail is the most popular facility on the Internet.

EMI (Electromagnetic interference). Signals that are radiated from electronic equipment that surround a subscriber such as computers that interfere with the signal quality of a call.

EMM (Entitlement Management Message). A satellite Conditional Access specifies customer entitlements. It is transmitted with the Entitlement Control Message.

Encryption/Decryption. Encryption is the scrambling of a communication signal for security purposes. Algorithms act on the signal to encrypt it before it is transmitted. When the signal is received, an algorithm is used to decrypt the encrypted signal.

EPG (Electronic Program Guide). A listing of all available TV programs covering a few days, which displays on a TV screen.

ESN (Electronic Serial Number). In US cellular systems, all mobile handsets have a unique ESN which is assigned at the time of manufacture. It is a permanent and unique identification number for mobile handsets.

ES (Elementary Stream). A DVB / MPEG-2, raw bit-stream consisting of digitized video or audio.

ES (End-System). A system where an ATM connection is terminated or initiated. An originating end-system initiates the ATM connection, and terminating end system terminates the ATM connection.

ESS (Electronic Switching System). A system used in telecommunications networks to switch call signals to the desired destination.

ESS (Extended Service Set). A logical collection of WLAN Access Points linked together.

ETR (Effective Transfer Rate). The maximum rate at which data can be sent after the data has been opimized for transfer by processes such as data compresssion.

ETSI (European Telecommunications Standards Institute). ETSI was founded in 1988 under the direction of the European Commission. Since 1988, the CEPT has gradually transferred its role in developing standards for European telecommunication over to ETSI.

External handover. Handover between...

1. Cells under the control of different BSCs but belonging to the same MSC.
   
2. Cells under the control of different MSCs.