Propagation Analysis with Ray Tracing Method for High Speed Trains Environment at 60 GHz

Applications of millimeter-wave (mm-wave) to high mobility wireless communication scenarios such as high speed trains (HSTs) have been discussed. In the HST scenarios, not only phase noise but also Doppler shift should be considered. In previous works, our proposed iterative phase noise compensation method was evaluated with a dynamic channel model with high Doppler shift. The efficacy of the iterative method, employing symbol level decision directed channel estimation (SDDCE), was demonstrated with the dynamic channel model. However, parameters of the channel model need to be obtained further for the HST environments. In this paper, we construct a linear HST environment, and analyse the propagation characteristics of the HST scenario with a ray tracing method at 60 GHz band. With the simulation, we obtain the received power, the K factor of the Rician model, delay spread, and angular spread characteristics of the HST environment. It is shown that the K factor is large when the distance between the transmit (Tx) and receive (Rx) antennas is short, and that when the distance between the Tx and Rx is large, the level of fading becomes large, which is much different from the indoor environment. We also complete the dynamic channel model with the obtained statistical parameters, which can simulate the dynamic channel fluctuation due to the Doppler shift.