Code-division multiple access (CDMA) is a technique of channel access. It is utilized by different radio communication technologies. In the CDMA technique, several transmitters can transmit data over a single communication channel. CDMA improves the utilization of accessible data transfer capacity as it sends over the entire frequency range and does not restrict the user’s frequency range. CDMA is utilized with BPSK and can be attached with QAM or OFDM.