Modeling and Simulation of CDMA Codes in Scilab

Mouhamed Fadel Diagana, Serigne Bira Gueye

Department of Physics, Faculty of Sciences and Techniques, Cheikh Anta Diop University, Dakar-Fann, Senegal.

DOI: 10.4236/ijcns.2015.87027                

Abstract

Prior to hardware implementation, simulation is an important step in the study of systems such as Direct Sequence Code Division Multiple Access (DS-CDMA). A useful technique is presented, allowing to model and simulate Linear Feedback Shift Register (LFSR) for CDMA. It uses the Scilab package and its modeling tool for dynamical systems Xcos. PN-Generators are designed for the quadrature-phase modulation and the Gold Code Generator for Global Positioning System (GPS). This study gives a great flexibility in the conception of LFSR and the analysis of Maximum Length Sequences (MLS) used by spread spectrum systems. Interesting results have been obtained, which allow the verification of generated sequences and their exploitation by signal processing tools.

Keywords

Code Division Multiple Access (CDMA), Linear Feedback Shift Register (LFSR), Maximum Length Sequence (MLS), Spread-Spectrum, Scilab, Xcos, Direct Sequence Spread Spectrum (DSSS)

Conflicts of Interest

The authors declare no conflicts of interest.

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