C
CAI
Common Air Interface; a standard developed for the UK’s public CT2 networks which enabled the same handset to be used on different networks
CAMEL
Customised Application for Mobile network Enhanced Logic; an IN feature in GSM networks that enables users to carry personal services with them when roaming into other networks that support CAMEL
CSE
CAMEL Service Environment
Capacity
A measure of a cellular network’s ability to support simultaneous calls
CB
Cell Broadcast
CC
Call Control; manages call connections
CCB
Customer Care and Billing
CCCH
Common Control Channels; a group of uplink and downlink channels between the MS and the BTS (see PCH, AGCH and RACH)
CCS7
Common Channel Signalling No. 7
CDMA
Code Division Multiple Access; also known as spread spectrum, CDMA cellular systems utilise a single frequency band for all traffic, differentiating the individual transmissions by assigning them unique codes before transmission. There are a number of variants of CDMA (see W-CDMA, B-CDMA, TD-SCDMA et al)
CDMAone
The first commercial CDMA cellular system; deployed in North America and Korea; also known as IS-95
CDMA2000
A member of the IMT-2000 3G family; backwardly compatible with cdmaOne
CDMA 1X
The first generation of cdma2000; the standardisation process indicated that there would be CDMA 2X and CDMA 3X but this no longer appears likely
CDMA 1X EV-DO
A variant of CDMA 1X which delivers data only
CDPD
Cellular Digital Packet Data; a packet switched data service largely deployed in the USA. The service uses idle analogue channels to carry the packetised information.
CDPSK
Coherent Differential Phase Shift Keying
CDR
Call Detail Records; the record made within the cellular network of all details of both incoming and outgoing calls made by subscribers, The CDR is passed to the billing system for action
Cell
The area covered by a cellular base station. A cell site may sectorise its antennas to service several cells from one locationCell site
The facility housing the transmitters/receivers, the antennas and associated equipment
Cell splitting
The process of converting a single cell to multiple cells by sectorising the antennas in the cell site or constructing additional cells within a cell site
CELP
Code Excited Linear Prediction; an analogue to digital voice coding scheme, there are a number of variants used in cellular systems
CEPT
Conference of European Posts and Telecommunications. A organisation of national posts, telegraphs and telephone administrations. Until 1988, when this work was take over by ETSI, the main European body for telecommunications standardisation. CEPT established the original GSM standardisation group
CF
Call Forwarding
CI
Carrier to Interference ratio
CIBER
Cellular Intercarrier Billing Exchange Roamer Record
CID
Caller Identification
Circuit switching
A method used in telecommunications where a temporary dedicated circuit of constant bandwidth is established between two distant endpoints in a network. Mainly used for voice traffic; the opposite of packet switching
CLID
Calling Line Identification
CLIP
Calling Line Identification Presentation
CLIR
Calling Line Identification Restriction
CM
Connection Management; is used to set up, maintain and take down call connections
CMOS
Complementary Metal Oxide Substrate
Codec
A word formed by combining coder and decoder the codec is a device which encodes and decodes signals. The voice codec in a cellular network converts voice signals into and back from bit strings. In GSM networks, in addition to the standard voice codec, it is possible to implement Half Rate (HR) codecs and Enhanced Full Rate (EFR) codecs
Control signal
A signal sent to a cellular phone from a base station or vice versa which carries information essential to the call but not including the audio portion of a conversation
CPE
Customer Premises Equipment; all the equipment on the end user’s side of the network interface
CPU
Central Processing Unit
CRC
Cyclic Redundancy Check
CRM
Customer Relationship Management
CSS
Customer Support System
CT
Cordless Telephony
CT0
Zero generation cordless telephony; the earliest domestic cordless phones which used analogue technology and which had severe limitations in terms of range and security
CT1
First generation cordless telephony; Improved analogue phones with greater range and security; a number of European nations produced CT1 standards
CT2
Second generation cordless telephony; Using digital technology CT2 phones offered greater range, improved security and a wide range of new functionalities. Used in both domestic and cordless PABX deployments, CT2 was standardised as an interim ETS but was overwhelmed by DECT
CT2-CAI
Second generation cordless telephony-common air interface
CTA
Cordless Terminal Adaptor; a DECT term
CTM
Cordless Terminal Mobility
CTR
Common Technical Regulation; part of the ETSI standardisation process
CUG
Closed User Group
The Consumer Mobile Glossary
Call barring
A service which enables users to bar certain incoming or outgoing calls on their mobile phones
Call timer
A service which keeps track of the amount of airtime being used by the subscriber on a cumulative basis
Call divert
The capability to divert incoming calls to another phone (fixed or mobile) or to an answering service
Call hold
The ability to put an ongoing call on hold whilst answering or making a second call
Caller ID
Caller Identification; displays the name/number of the person calling a mobile phone. Also known as CLI
CLI
See Caller ID
CLR
Clear; the key on a cellular phone which is pressed to remove information from the display
