The Methodology Of Scatterer Modeling And Its Research In The Wireless Channel Of Connected Vehicles

The structure that causes the deviation of the trajectory of the propagated electro-magnetic wave is called scatterer,and the physical phenomenon as the deviation of the trajectory of the propagated electromagnetic wave is called scattering,so the modeling of a scatterer is the process of modeling its scattering.The scatterer modeling is of great sig-nificance to the development of the Connected Vehicle.The main reason is that the deep understanding of the characteristics of the radio wave propagation is the basic guarantee for the design and optimization of any wireless communication system in the Connected Vehicle.The characteristics of the radio wave propagation(or wireless channel)of the Connected Vehicle scenario depend on the type and location distribution of the scatterers.Different from traditional cells,wireless channels in the Connected Vehicle have com-plex and diverse characteristics.This complexity is due to the complexity of scatterers in the Connected Vehicle scenario,including narrow urban roads and dense buildings,traffic signs alongside roads,and high-speed moving cars.Despite decades of efforts,people's awareness of the wireless channel characteristics of the Connected Vehicle has made great progress,but it is still a hot topic in academic and industrial research.One of the breakthroughs in this research hotspot is the study of efficient and high-precision modeling methods for scatterers.As an inseparable and important part of wireless channel research in Connected Vehicle,scatterer modeling and wireless channel research jointly undertake the design,planning and deployment of network wireless communication system of Connected Ve-hicle.The existing research on the modeling of the Connected Vehicle wireless channel and the modeling of related scatterers still has the following limitations:1)The statistical model based on the measured data of the wireless channel is the main-stream method for studying the wireless channel of the Connected Vehicle.The output of the model is the statistical value of the key parameters of the wireless channel in Connected Vehicle.However,the limitation of the model itself does not energize the influence of specific scatterers in specific scenes.The main reason for the limitation of the statistical model comes from the inherent defects of the model itself,that is,the process of model modeling needs to combine a large amount of channel data to extract statistics.So it is hard to isolate the effects of specific scatterers from the channel.The wireless channel analysis of the Connected Vehicle based on the statistical model is difficult to do channel quantitative analysis in specific physical scenario and scatterer distribution.2)Deterministic modeling is an important tool for studying vehicular wireless channels,most people only know how to use it.Admittedly,deterministic modeling has the advantage of being easy to program,low cost,and versatile.But the understanding of the radio propagation behind deterministic modeling directly determines the accuracy of the simulation.However,the existing radio wave propagation models are widely applicable,and they often have a certain deviation in some specific environments.3)The scatterer modeling has always been a missing part of the Connected Vehicle wire-less channel simulation.Mainly because the modeling of the roadside scatterer is quite different as the profile of the scatterer is complicated.It has to say that scatterer model-ing does not have a "cost-effective" for the narrow-band wireless channel simulation.With the development of wireless communication systems and the strong demand for refined channel modeling,the importance of scatterers in Connected Vehicle channels has become increasingly important.In view of the above problems,this paper proposes a new method for modeling scatterers in the Connected Vehicle.The ultimate goal is to achieve efficient implantation of scatterers in the Connected Vehicle wireless channel simulation.The research process involves the deepening of deterministic modeling theory,the construction of specialized material measurement platforms and the theories of scatterer modeling.Main tasks as follows:1)We propose that using the scattering centers to model the scattering characteristics of road scatterers such as traffic signs.In this process,the road scatterer was modeled using the scattering center theory in the radar field.In addition,the concept of effective region was proposed to theoretically model the scattering of street lampposts,and the importance of street lamppost group scattering modeling was proposed and the corresponding mathematical closed expression was derived.2)The theoretical method of predicting the bistatic near-field scattering of vehicles us-ing bistatic scattering centers was proposed for the vehicle scattering modeling.In the process,the prediction error of the bistatic scattering predicted by monostatic s-cattering centers is eliminated.Therefore,the above process improves the research of vehicle effects on the channels.3)For the modeling of building scatterers,this paper proposes to model the building s-catterers from the study of the wave propagation mechanism occurring on the surface of building scatterers.The specific research results are the reflection and surface s-cattering characteristic parameters(specifically,material surface roughness,dielectric constant and surface scattering characteristic parameters)from rough surface mea-surement.Through the investigation and parameter extraction of common materials of the Connected Vehicle,a corresponding material database was finally formed,which can be used for the implantation of scatterers in the future millimeter-wave wireless channel simulation of the Connected Vehicle.4)Based on the modeling method of road scatterers,a layered channel model was pro-posed to successfully implant road scatterers into ray tracing simulation.Based on the above research,the frontier exploration of the millimeter wave broadband wireless channel in Connected Vehicle scenario was carried out.In summary,from the innovation of theory,this paper pioneered the new methods and new theories of scatterer modeling,and proposed a layered channel model combining scatterer model and ray tracing algorithm.Based on the above modeling theory,the millimeter wave wireless channel character:istics of the Connected Vehicle tunnel was simulated,from the innovation of methodology,the research on scatterers is divided into road scatterers,automobile bodies and building scatterers,respectively.In the method,the conventional cognition is broken.The modeling method of scattering center points is proposed to make up for the deficiency of the existing Connected Vehicle channels research.The proposed scatterer model takes into account both computational efficiency and accuracy.