Simulation of GDFT for CDMA
نویسندگان
چکیده
Generalized Discrete Fourier Transform (GDFT) with nonlinear phase is a complex valued, constant modulus orthogonal function set. GDFT can be effectively used discrete multi-tone (DMT), orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA) communication systems. The constant modulus transforms like discrete Fourier transform (DFT), Walsh transform, and Gold codes have been successfully used in above mentioned applications over several decades. However, these transforms are suffering from low cross-correlation features. This problem can be addressed by using GDFT transform. This paper describes the MATLAB simulation of GDFT for code division multiple access (CDMA). We have also implemented Gold, Walsh and DFT codes. Their performance is analyzed and compared on the basis of various parameters such as Maximum Value of Out-of-Phase AutoCorrelation, Maximum Value of Out-of-Phase CrossCorrelation, Mean-Square Value of Auto-Correlation, MeanSquare Value of Cross-Correlation and merit factor.
منابع مشابه
Optimization of Generalized Discrete Fourier Transform for CDMA
Generalized Discrete Fourier Transform (GDFT) with non-linear phase is a complex valued, constant modulus orthogonal function set. GDFT can be effectively used in several engineering applications, including discrete multi-tone (DMT), orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA) communication systems. The constant modulus transforms like discrete Fou...
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