Time-scale domain characterization of nonstationary wideband vehicle-to-vehicle propagation channel

The design and deployment of efficient vehicle-to-vehicle (V2V) communications systems require the knowledge of the propagation channel in which it will operate. Due to the mobility of the transmitter/receiver terminals as well as the existence of dynamic scatterers, the V2V channel is nonstationary. To account for the nonstationarity, channel characterization methods that employs the non wide-sense stationary uncorrelated scattering (non-WSSUS) approach are often desired. More also the inadequacy of the Doppler shift operator to properly account for frequency variation effects by the wideband channel operator implies that the time-frequency characterization methods that employ the Doppler shift operator are not appropriate for wideband V2V channels. In this paper we present the time-scale domain characterization of the non-WSSUS channel which employs time scaling operator to account for frequency variation and also emphasizes on the non-stationary property of the channel. The non-WSSUS statistical property termed local sense stationary uncorrelated scattering (LSSUS) is employed. The effect of the channel nonstationarity on the channel capacity is also addressed. From the simulated example, it is inferred that the assumption of ergodic capacity depend on the number of available independent fades which invariably depend on the degree of the V2V channel nonstationarity.