CDMA (Code Division Multiple Access)- is a digital wireless technology with a code division of channels. Initially, CDMA was developed and used for USA armed forces. Then, American company Qualcomm on the basis of this technology generated first CDMA standard – cdmaOne. CDMA technology was further evolved in cdma2000 standard.
The simplest explanation of the communication process is following: speech is converted and transmitted as a spread-spectrum signal that can be received, i.e. allocated from the total number of channels only using a unique code. All data is transmitted over a broad band, many signals are transmitted simultaneously over the same channel. Code channels division at the multiple access protects the data from interception, frequency interference and listening.
cdma2000 standard provides a high quality of communications and a large quantity of value-added services therefore it becomes more popular in the world replacing analogue standards NMT and AMPS and becoming a serious competitor to GSM standard.
Nowadays more than 130 million consumers practically all over the world use telecommunications services of cdma2000 standard. Growth rates of those who are devoted to this standard are so high that in the near future they can reach the number of GSM subscribers.