Study On The Verification Method Of Wireless Fading Channel Model

With the continuous development of information science,wireless communication technology has made great progress in recent years,and at the same time,wireless communication systems have become more and more complex.As an important part of a wireless communication system,the performance of the wireless channel directly affects the communication quality of the system.In practical applications,due to the complex and changeable environment in which electromagnetic waves propagate in space,the transmission path and time that the signal travels from the sender to the receiver are different,resulting in multipath fading characteristics.Scholars have done a lot of research on wireless channel modeling,and have proposed Rayleigh fading model,Rician fading model,Nakagami model,log normal model,constant model,etc.Among them,the Rayleigh channel and the Rician channel are two types that are very typical in small-scale fading.It describes that in the process of wireless signal transmission,electromagnetic waves arrive through reflection,refraction,and scattering due to obstruction of buildings or other objects.The worst case at the receiving end is the basis for studying the wireless channel model.After the simulation of the wireless channel model,in order to test its accuracy and stability,it needs to be verified and evaluated.This paper first studies the fading characteristics of wireless channels.After extracting the first-order statistical characteristics of the channel,the channels are classified according to the amplitude distribution of the envelope,and are roughly divided into constant models,pure Doppler models,Rayleigh models,Rician models,Nakagami models,and log-normal models and Suzuki models.These models correspond to different channel environments and applicable scenarios,respectively.Then,from the perspective of power spectrum characteristics,three classical methods for extracting wireless channel power spectrum parameters are realized through computer simulation,including the periodic graph method,correlation function method,and welch method.The appropriate power spectrum extraction method is selected by analyzing the simulation results.Then take Rayleigh channel as an example,introduce the characteristics of Rayleigh fading channel model,analyze its first-order and second-order statistical characteristics in detail,and propose a comprehensive verification method of Rayleigh fading channel model based on error analysis.The characteristics are verified to obey the Rayleigh distribution,and then the Doppler power spectrum distribution is used to verify which Rayleigh fading model belongs.Extract the Doppler power spectral density function of the complex sequence of the fading channel,calculate the logarithmic mean square energy error(LMSEE)of the theoretical Doppler power spectral density,and use LMSEE to determine the type of the Doppler power spectrum distribution to complete the given Validation of fading channel model.A large number of simulation experiments and physical verifications have been performed,and the results show that the recognition accuracy rate is more than 98%,indicating the effectiveness and stability of the method.Finally,a comprehensive verification method of wireless fading channel model based on goodness-of-fit test is proposed.The method uses the cumulative distribution function of the Doppler power spectrum as the test object.The feasibility of the method for Rayleigh channel and Rician channel was verified respectively.The accuracy and stability of the method were proved through a lot of repetitive experiments,and the algorithm was compared with the verification algorithm proposed based on error analysis.Performance advantage with additive Gaussian white noise.