Small Set Orthogonal Kasami codes for CDMA system

Present day communication uses a technology called Code Division Multiple Access (CDMA) to serve a large number of users simultaneously and to ensure that all of them utilize the entire available channel bandwidth. In this particular access system, each user is identified by a unique code. While assigning distinct spreading code to each user, our objective is to find out as many codes as possible to serve a huge number of users. However, we must also make sure that the cross-correlation value between any pair of distinct spreading codes should be as low as possible in order to permit a very less multi-user interference. In this paper, we have proposed Small Set Orthogonal Kasami sequence which is capable of providing more number of different codes as compared to popularly used orthogonal spreading code in synchronous CDMA system such as Walsh code. We have developed one code generation algorithm and also studied the Bit Error Rate (BER) performances of different orthogonal codes in multi-user scenario under different Signal to Noise Ratio (SNR).

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