Doppler Power Spectra for 3D Vehicle-to-Vehicle Channels With Moving Scatterers

A 3-D vehicle-to-vehicle (V2V) channel model composed by the line-of-sight, single-bounced and double-bounced rays with local scatterers moving in random velocities and directions is proposed in this paper. Based on the 3-D model, the complex channel gain and the autocorrelation function (ACF) are derived. The Doppler power spectral density (PSD) can be obtained by taking the Fourier transform to the ACF. As special cases, the proposed model can be applied to the 3-D fixed-to-vehicle (F2V) and fixed-to-fixed (F2F) scenarios at different carrier frequencies. The 2-D V2V, F2V, and F2F ACFs and Doppler PSDs can be obtained from the proposed 3-D model. Good agreements are shown between the theoretical and available measured Doppler PSDs in different scenarios in this paper.