Improved correlation of Generalized DFT with nonlinear phase for OFDM and CDMA Communications

Recently, Generalized Discrete Fourier Transform (GDFT) has been forwarded as the theoretical framework to design a variety of constant modulus orthogonal complex transforms with non-linear phase. In this paper, we evaluate the auto- and cross-correlation properties of several GDFT solutions and compare them with the popular code families like Gold, Walsh and DFT. It is shown that the GDFT brings significant correlation performance improvements over known code families. We predict that GDFT based OFDM and CDMA solutions will offer performance improvements in multicarrier communications systems of the future.