A new channel simulation model for fast moving terminals
In the current broadband multimedia applications, researchers and practitioners have mainly focused their designs on coping with static or slowly evolving traffic demands. Even though many such applications involve fast moving terminals, fast moving traffic conditions have not yet been taken into account which results in unrealistic simulations. It is therefore imperative to design a new channel simulation model in the fast moving scenario for systematic performance evaluations. Existing models for simulation of fast fading channels use only maximum Doppler frequency to represent the effect caused by the maximum moving speed of the terminal without considering the effect of the changes in the magnitude and the direction of motion. Such simplified assumption is in strong contrast with real-world communication systems in which the velocity of a moving terminal may change in both magnitude and direction in the duration of transmission. We propose in this paper a novel model for the simulation of Rayleigh fading channel in fast moving scenario. The model is based on the sum-of-sinusoids method and accounts for the fresh channel characteristics due to the changes in the magnitude and direction of the terminal's velocity on an instant-by-instant basis. The statistical analysis of the proposed channel model demonstrates that the proposed model not only is more suitable for simulating fast moving scenario, but also can be considered as a more general model for Rayleigh fading channels. The simulation results demonstrate the advantages and the efficiency of the proposed model for characterizing more practical communication systems.