C- Glossary

Call Forwarding - A feature allowing the subscriber to forward a call to another telephone number.
Call Processing - The complete process of routing, originating, terminating cellular telephone calls, along with the necessary billing and statistical collection processes.
Call Record - A record stored on DAS tape containing mobile number, dialed digits, time stamp information, and other data needed to bill or 'ticket' a cellular telephone call.
Call Setup - The call processing events that occur during the time a call is being established, but not yet connected.
Call Waiting - A feature allowing the subscriber to be alerted of another call during a current conversation. User can answer the call waiting, but cannot connect all parties (connecting all parties is considered a conference call).
Carrier - The operating frequency of a wireless system. A fixed frequency radio signal which is shifted up and down (modulated) in either frequency (FM) or level (AM) by the audio signal.
CDMA - Code Division Multiple Access. In a CDMA system, each voice circuit is labeled with a unique code and transmitted on a single channel simultaneously along with many other coded voice circuits. The receiver uses the same code to recover the signal from the noise. The only distinctions between the multiple voice circuits are the assigned codes. The channel is typically very wide with each voice circuit occupying the entire channel bandwidth. This system used 1.23 MHz wide channel sets. The full vocoder rate is 8.55 Kbits/sec, but voice activity detection and variable rate coding can cut the data rate to 1200 bits/sec. A very robust and secure channel can be established, even for an extremely low-power signal-theoretically, the signal can be weaker than the noise floor.
Example:CDMA channel
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1.25MHz     |   64 different voice circuits   |

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64 different voice circuits can be simultaneously transmitted on the same channel. More impressively, by using different codes, a number of different channels can simultaneously share the same spectrum, without interfering with each other. The voice circuits are identified by their assigned codes.