CDMA (code division multiple access) refers to digital cellular telephony systems that make use of a form of multiplexing and a method of multiple access that does not divide up the channel by time or frequency but instead encodes data with a special code associated with each channel and uses the constructive interference properties of the special codes to perform the multiplexing.
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 communications chips 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.
CDMA should not be confused with, and is not compatible with Wideband Code Division Multiple Access (W-CDMA).Related Articles