Recently, the Generalized Discrete Fourier Transform (GDFT) with nonlinear phase was introduced to improve the traditional Discrete Fourier Transform (DFT). We take advantage of the phase shaping function (PSF) of GDFT framework to optimize auto- and cross-correlation properties of OFDM frames used to generate radar waveforms. The superior performance of the GDFT MIMO radar waveforms over multifrequency complementary phase coded (MCPC) and Oppermann code families are presented in this paper. GDFT MIMO radar waveforms may be employed in the future as an efficient upgrade to the DFT based technologies.