Research On VHF Channel Modeling Methods

With more and more research on ultrashort wave communication frequency band,its application is gradually widespread.Ultrashort wave communication plays an important role in modern communication research,especially in the field of military comm unication,and has become a mode of great significance.According to the development of ultra-short wave wireless communication technology,it is necessary to design a realistic ultra-short wave communication system to simulate the actual ultra-short wave communication environment.Therefore,in this paper,based on the measured data and the existing research on the ultra-short wave channel model,the channel modeling and simulation work is carried out for the ultra-short wave channel with restricted Dopple r power spectrum,and the visualization interface is also established.First,in order to describe the wireless channel propagation characteristics in complicated radio environment,a novel channel model with restricted Doppler power spectrum is proposed i n this paper.The principles and implementation methods of three modeling methods are discussed in details,including single-path filtering method,dual-path filtering method,and improved splicing method.The comparison analysis of autocorrelation function,Doppler spectrum,algorithm complexity and memory occupation of the three typical models that generate the channel stochastic process are also presented.The results show that,when simulating a restricted Doppler power spectrum,the root mean square er ror of the autocorrelation function of the improved splicing method is significantly lower than the other two methods with the digital filters and Hilbert converters left out.Meanwhile,the single-path filtering method leads to the lowest complexity cost.The contributions in the paper can help to select the constrained Doppler spectrum model and provide a reference for more complicated Doppler power spectrum modeling.Secondly,based on the above work,the COST207 model and the measured channel model are modeled and simulated,and their power delay profile,Doppler spectrum,autocorrelation functions and scattering functions are analyzed.By comparing with the theoretical values,the reasonableness of the chosen method for modeling the ultra-short wave channel model based on the constrained Doppler power spectrum in this paper is illustrated,which provides a new perspective on the real-measured channel modeling work.Finally,most of the results of this project work are shown,and the visualization interface is shown to introduce its functions and structure.This paper provides ideas for the treatment of the restricted Doppler power spectrum in the face of practical channel measurement and modeling works,and lays the foundation for the development of commu nication test equipment.