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This paper investigates the different sequences that can be used in direct sequence divisionmultiple access (DS- CDMA) systems. The auto-correlation, cross correlation, the mean square correlationmeasurements ( RAC, RcC ) and merit factor (MF) are used for evaluating the performance of differentspreading sequences. The results obtained small set of Kasami sequences is the most effective of binarysequences families in terms of correlation measure, but this set suffers from the limited number ofsequences. Overall among orthogonal category, Orthogonal Gold sequences and Golay complementarysequences are a better candidate in synchronous CDMA applications.

In this paper, we present the performances comparison, in terms of Bit Error Rate (BER), of different spreading codes largely used in Direct Sequence Code Division Multiple Access system DS-CDMA. Different tests were performed on AWGN Channel with BPSK modulation. In fact, orthogonal and Pseudo Noise (PN) codes were tested using synchronous communication model. Their performances were compared based on the code length and number of users. It has been found that the performances of the orthogonal codes are much better than PN codes. However, among all orthogonal sequences, Walsh-Hadamard sequence has the best performances in terms of BER. For PN codes, large set of Kasami has poor performances.