Glossary  >  Code Division Multiple Access (CDMA)

Code Division Multiple Access (CDMA)


Code Division Multiple Access (CDMA) is a spread-spectrum technology standard used in digital networks to allow full bandwidth. CDMA uses a form of multiplexing where several transmitters can simultaneously send a signal over a single communication channel.

This is because CDMA employs the Direct Sequence Spread Spectrum (DSSS) technique, whereby unless a transmitter and receiver use the same spreading code, a signal cannot be decoded.

CDMA ensures multiple users can access a base station through the same channel without mutual interference, assigning each user a unique code rather than a different time slot or frequency channel.

This also enhances voice and data communication capability and security for users.

CDMA is commonly used in Ultra High Frequency (UHF) cellular systems in the spectrum 800 MHz to 1.9 GHz and as the access method in many mobile phone standards.

For instance, the Universal Mobile Telecommunications System (UMTS) — the 3G standard used by GSM carriers, employs W-CDMA (Wideband CDMA) in its radio frequency communication technologies.

Example of Code Division Multiple Access in a sentence

"By allowing more users access at any given time, CDMA has greatly improved communication capacity."

Related Terms for Code Division Multiple Access

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