Wireless Technology Terms Glossary and Dictionary [C-D]
C/I: Carrier-to-Interference ratio
Carrier-to-Interference ratio (C/I) is the ratio of power in an RF carrier to the interference power in the channel.
C/N: Carrier-to-Noise ratio
Carrier-to-Noise ratio (C/N) is the ratio of power in an RF carrier to the noise power in the channel. Carrier-to-Noise ratio indicates the difference in amplitude between the desired radio frequency (RF) carrier and the noise in a portion of the spectrum.
CAI: Common Air Interface
Common Air Interface (CAI) is a set of open standards describing the physical and logical characteristics of a link between a base station and a mobile station. These standards are used by infrastructure and handset manufactures to design and build equipment that is capable of interoperating with each other's systems.
Call Diversion is the feature used to divert incoming calls on a mobile phone to any other telephone or to a Mailbox/Combox on a GSM system.
CAMEL: Customized Application for Mobile Network Enhanced Logic
Customized Application for Mobile Network Enhanced Logic (CAMEL) refers to a set of 3rd Generation APIs based on ETSI recommendation TS 129 078 (V3.3.0). CAMEL finds widespread applicability in developing applications for next generation networks converging Phase 2+ GSM/UMTS. CAMEL allows roaming subscribers access to their full portfolio of IN services. CAMEL GSM phase 2+ connects the home and visited mobile networks to various Intelligent Network (IN) platforms used throughout national networks to provide features such as Pre-Paid Calling, personal Numbering and more complex location dependent services. As a result, CAMEL is a relatively inexpensive method of allowing telecom operators to add new services to the existing network infrastructure.
CAP CODE is a pager's unique electronic identification number.
Carrier means the continuous frequency capable of being modulated or impressed with a second signal.
Carrier Frequency refers to the nominal frequency of a carrier wave, the frequency of the unmodulated electrical wave at the output of an amplitude modulated, the center frequency of a frequency modulation signal, frequency modulated, or phase modulated transmitter of the output of a transmitter when the modulation is zero.
Carrier recovery is a technique for extracting the RF carrier from a modulated signal so that it can be reinserted and used to recover the modulating signal.
CBC: Cell Broadcast Center
Cell Broadcast Center (CBC) is the functional entity within the mobile network that is responsible for the generation of cell broadcast information.
CBCH: Cell Broadcast Channel
Cell Broadcast Channel (CBCH) is a downlink point-to-multipoint logical channel in a GSM system used to broadcast user information from a service center to mobile stations listening in a given cell area.
Chase Combining (CC), also known as Convolution Code, is one of the two fundamental forms of Hybrid ARQ (HARQ). The other one is an incremental redundancy (IR). In Chase combining, each retransmission repeats the first transmission or part of it. While Chase combining is sufficient to make AMC robust, IR offers the potential for better performance with high initial code rates and FER operating points at the cost of additional memory and decoding complexity.
CCDF: Complementary Cumulative Distribution Function
Complementary Cumulative Distribution Function (CCDF) is a method used to characterize the peak power statistics of a digitally modulated signal. The CCDF curve can be used to determine design parameters for CDMA systems (such as the amount of back-off to run in a power amplifier).
CCH: Control Channel
Control Channel (CCH) refers the channels that transmit signaling and control information between the network and the mobile stations.
CCI: Co-Channel Interference
Co-channel interference (CCI) refers to interference from 2 different radio stations on the same frequency. CCI is one of the major limitations in cellular and PCS wireless telephone networks. In the case of TDMA networks, such as GSM/GPRS or NADC (otherwise known as "IS-136"), the co-channel interference is mainly caused by the spectrum allocated for the system being reused multiple times ("frequency reuse"). Co-channel interference, when not minimized, decreases the ratio of carrier to interference powers (C/I) at the periphery of cells, causing diminished system capacity, more frequent handoffs, and dropped calls.
CCITT: International Telegraph and Telephone Consultative Committee
CCITT is the abreviation of the International Telegraph and Telephone Consultative Committee in France. CCITT is standards body based in Geneva that publishes "recommendations" on standards used throughout the world communication industry.
CCM: Counter mode with Cipher-block chaining Message authentication code
Counter mode with Cipher-block chaining Message authentication code (CCM) is an encryption protocol in the 802.11i standard. The CCM protocol (CCMP) is based upon the CCM mode of the AES encryption algorithm and utilizes 128-bit keys, with a 48-bit initialization vector (IV) for replay detection.
CCMP: Counter mode with Cipher-block chaining Message authentication code
Protocol Counter mode with Cipher-block chaining Message authentication code Protocol(CCMP) is an encryption protocol in the 802.11i standard. The CCMP is based upon the CCM mode of the AES encryption algorithm and utilizes 128-bit keys, with a 48-bit initialization vector (IV) for replay detection.
CCSA: China Communications Standards Association
China Communications Standards Association (CCSA) is a P. R. China gorvenment sponsored organization to establish a nationally unified standards in the communication technologies. With the approval of the Ministry of Information Industries (MII) and Standardization Administration of China and the Civil Affairs Ministry, China Communications Standards Associatio (CCSA) was founded in December 18, 2002.
CCTrCH: Coded Composite Transport Channel
Coded Composite Transport Channel (CCTrCH), a technology in the UMTS physical layer, is the connection between Transport Channel and Physical Channel which results in a data stream from encoding and multiplexing of one or several transport channels.
CDF: Cumulative Distribution Function
Cumulative Distribution Function (CDF) describes the probability distribution of a real-valued random variable, X. The Kolmogorov-Smirnov test is based on cumulative distribution functions and can be used to test to see whether two empirical distributions are different or whether an empirical distribution is different from an ideal distribution.
CDG: CDMA Development Group
CDMA Development Group (CDG) is an international consortium of companies who have joined together to lead the adoption and evolution of 3G CDMA wireless systems around the world. The CDG is comprised of CDMA service providers and manufacturers, application developers and content providers. By working together, the members help to ensure interoperability among systems, while expediting the availability of 3G CDMA technology to consumers.
CDM: Code Division Multiplexing
Code Division Multiplexing or Code Division Multiplex (CDM) is a technique in which each channel transmits its bits as a coded channel-specific sequence of pulses. This coded transmission typically is accomplished by transmitting a unique time-dependent series of short pulses, which are placed within chip times within the larger bit time. All channels, each with a different code, can be transmitted on the same fiber and asynchronously demultiplxed. Other widely used multiple access techniques are Time Division Multiple Access (TDMA) and Frequency Division Multiple Access (FDMA).
CDMA: Code Division Multiple Access
Code Division Multiple Access (CDMA) is a second generation (2G) cellular technology defined by Qualcomm in IS-95 and IS-2000. Other widely used multiple access techniques for cellular are Time Division Multiple Access (TDMA) and Frequency Division Multiple Access (FDMA). CDMA technologies are evolving into CDMA2000 to meet the challenges. CDMA2000 is the 3rd Generation solution based on IS-95.
Code Division Multiple Access 2000 (CDMA2000 or CDMA-2000) is the 3rd Generation solution based on CDMA IS-95, which supports 3G services as defined by the ITU 3G standards IMT-2000. CDMA2000 defines both an air interface and a core network. CDMA2000 has already been implemented as an evolutionary step from cdmaOne as CDMA2000 provides full backward compatibility with IS-95B.
cdmaOne is the commercial name for a CDMA (Code Division Multiple Access) system defined by the consortium including Qualcomm, AT&T Wireless and Motorola. The IS-95 standard is part of cdmaOne as the air interface.
CDP: Code Domain Power
Code Domain Power (CDP) is a measurement of the power contained in each Walsh coded channel in CDMA signals. The CDP measurement is beneficial in troubleshooting CDMA transmitter designs.