Code-Division Multiple Access (CDMA)
Short for Code-Division Multiple Access, a digital cellular technology that uses spread-spectrum techniques. Unlike competing systems, such as GSM, that use TDMA, CDMA does not assign a specific frequency to each user. Instead, every channel uses the full available spectrum. Individual conversations are encoded with a pseudo-random digital sequence.
CDMA consistently provides better capacity for voice and data communications than other commercial mobile technologies, allowing more subscribers to connect at any given time, and it is the common platform on which 3G technologies are built.
CDMA is a military technology first used during World War II by English allies to foil German attempts at jamming transmissions. The allies decided to transmit over several frequencies, instead of one, making it difficult for the Germans to pick up the complete signal. Because Qualcomm created communicationschips for CDMA technology, it was privy to the classified information. Once the information became public, Qualcomm claimed patents on the technology and became the first to commercialize it.
Another name for 1xRTT.
- Content Delivery Network (CDN)
CDN is short for content delivery network. A content delivery network (CDN) is a system of distributed servers (network) that deliver webpages and other Web content to a user based on the geographic locations of the user, the origin of the webpage and a content delivery server. This service is effective in speeding the delivery […]
Short for Cellular Digital Packet Data, a data transmission technology developed for use on cellular phone frequencies. CDPD uses unused cellular channels (in the 800- to 900-MHz range) to transmit data in packets. This technology offers data transfer rates of up to 19.2 Kbps, quicker call set up, and better error correction than using modems […]
- CD-I (Compact Disc-Interactive)
A software and hardware standard developed jointly by Philips International and Sony Corporation for storing video, audio, and binary data on compact optical disks. It supports 552MB (megabytes) of binary data and specifies several different types of video and audio encoding formats. Unlike conventional CD-ROM drives, CD-I drives have a built-in microprocessor to handle many […]
A type of CD format that is enhanced to support multisessions. CD-Plus can store both video and audio data.