Simulation And Modeling For Two Typical Kinds Of Wireless Fading Channels

Wireless communication is nowadays one of the most important types of communication. The transmission characteristics of the channel is considered firstly, during the design of a wireless communication system, so the wireless fading channel modeling and simulation for wireless communication is important. With many of simulation models are proposed, ITS model for wideband HF channel and the multi-state model on land mobile satellite channel have been widely used.The performance of wireless communication is mainly affected by:multipath, the Doppler effects and shadowing. The main consideration for wireless fading channel models is factors just mentioned before, and then get the expected model through the existing mathematical theory with the measured data curve fitting as accurately as possible.Curve fitting is an very important application in the channel modeling theory, wireless fading channel models are derived by using the method of curve fitting the mathematical model of the channel. The performance of channel model validation is verified mainly through the statistical properties of the measured data. For wideband HF channel, the channel scattering function is the most important indicator for measuring the performance, for land mobile satellite channels the level crossing rate and average fade duration statistical properties will always is considered.ITS model is the most classic model of the wideband HF channel, but because of the complex form the delay power distribution function, the simulation is more difficult. For curve fitting theory, the new delay power distribution function is proposed based on Nakagami-m distribution, also the closed expression of the delay power distribution function is given, the new simulation model compared with the ITS models has similar statistical properties.For the land mobile satellite channel, the classic models are C. Loo model, LUTZ model and Corazza model, and multi-state model proposed in recently, which is better fitted with the characteristics of the channel compared to the other classical models. These existing models is analyzed in this paper, the parameter fitting method based on the satellite elevation angle is applied in the multi-state model which reduces the dependence of the measured data and the new model have the similar performance with the original model.