CDMA

Code division multiple access (CDMA) is a form of pemultipleksan (not a pemodulasian scheme) and a common access method that divides the channel is not based on time (as in TDMA) or frequency (as in FDMA), but by way of coding data with a code specifically associated with each channel that exists and use properties of constructive interference of the special codes to perform pemultipleksan.

CDMA also refers to digital cellular telephone system that uses a shared access scheme, such as that initiated by Qualcomm.

CDMA is a military technology first used in World War II by English allies to foil German efforts disrupt their transmission. Allies decided to transmit not only on one frequency, but at some frequency, Germany made it difficult to capture the full signal.

Since then CDMA is used in many communications systems, including the Global Positioning System (GPS) and the OmniTRACS satellite system for transportation logistics. Final system was designed and built by Qualcomm, and the embryo is helping Qualcomm engineers to find the Soft Handoff and power control quickly, the technology needed to make practical and efficient CDMA for terrestrial mobile communications.

CDMA Benefits

CDMA technology itself has many advantages when applied in mobile systems. The benefits include:

* Only need one radio required for some sectors / cell
* Do not need equalizer to overcome the signal spectrum disorders
* Can be joined with other access methods, does not require a timer (guard time) to see the range of time and guard band (guard band) to keep the intervention antarkanal
* Does not require frequency allocation and management of
* Has a fine capacity to restrict access to users
* Have the protection of the process of tapping