Abstract: Code Division Multiple Access (CDMA) have a key role in vast number of research activities. CDMA is a spread spectrum technology for the transmission of radio signals in telecommunication system. In CDMA multiple users can transmit the data simultaneously in a channel using same frequency. Each user is assigned with a unique code for transmission. The performance of any CDMA system can be determined by the choice of the spreading codes which are used as a signature code for the users in such a system. The choice of spreading code sequence is vital for resistance against interference with other areas and against interference with multiple users. Sequences of code that desires to be as different but at the same time can be easily reproduced at the reception signal can be recovered. This multiple access technique requires neither the frequency management nor the time management. This paper deals with the comparison of different spreading codes based on the autocorrelation and crosscorrelation properties. These spreading codes provide security for the data transmission.
Keywords: Spread spectrum, Spreading codes, Autocorrelation, Crosscorrelation, Code Division Multiple Access, Optical Code Division Multiple Access, Pseudo Noise code.