3-D Space-Time-Frequency Correlation Functions of Mobile-to-Mobile Radio Channels

In this paper, we present a double-ring mobile-to-mobile channel model based upon a three-dimensional (3D) space-time-frequency correlation function via combining the antenna pattern, Doppler shift, and delay profile. This 3-D correlation function results in the probability density distribution (PDF) of an extra elevation angle (EA) being taken into the antenna pattern and the Doppler shift consideration. Four types of the EA PDF, Aulin, Parsons, Qu-Yeap, and uniform models, have been discussed. It is revealed through computer simulations that the 3-D scattering scenario outperforms the two-dimensional environment in terms of the cross-correlation for all four types of the EA PDFs. Furthermore, we find that the performance of the uniform model is better than the others when the radius of the circular antenna array is more than 0.5 times of the propagation wavelength, or 7.5 cm for a 2 GHz carrier frequency.