Vehicle-to-vehicle Wireless Communication Channel Modeling And MIMO System Analysis

In recent years,with the rapid development of the wireless communication business and the emerging broadband mobile Internet access technology,the optimization of wireless communication system becomes very important.In practice,the understanding of the wireless channel has been the foundation for designing wireless transmission technology with high performance and spectrum efficiency.As one of the key technologies for the fifth generation(5G)in modern and future mobile communications,large scale multiple input multiple output(MIMO)has manifested enormous superiorities in the advancement of channel capacity and spectrum utilization rate.MIMO system performances mainly depend on the wireless fading channel and transmitter-receiver array elements.The characteristics of wireless channel have great influence on the signal transmission.Therefore,it is very necessary for the channel modeling of the electromagnetic signal transmission between the base station(BS)and mobile station(MS).This paper mainly focuses on the vehicle-to-vehicle wireless communication channel modeling and MIMO system analysis,and further analysis of MIMO antenna arrays,Doppler shift(DS),the power spectral density(PSD),spatial fading correlation(SFC),channel capacity and the influence on the performance of the system,which makes a theoretical basis for the performance analysis of the wireless mobile communication system through the modeling of vehicular channel in spatial domain.In this thesis,the research work mainly is divided into the following three aspects:Firstly,To establish scattering models that match realistic street transmission scenarios for more efficient M2M mobile communication systems,a modified multi-bounced channel model based on EBSBM is provided,in which the concept of equivalent scattering point is assumed.The multi-bounced propagation paths are considered as an one-bounced ellipse scattering path and characteristics of the model are further analyzed.General formulations of several important parameters such as the probability density function(PDF)of the angle-of-departure(AOD)and angle-of-arrival(AOA)are derived,which are applied to the performance of MIMO system employing a circular array antenna.Doppler frequency distribution is also taken into account.The results show good agreement with the previously models,which validates the rationality of our EBMBM model.Secondly,in order to overcome the limitations of the above channel model,a new wide-band MIMO fading channel model for annular road vehicular-to-vehicular(V2V)non-line of sight(NLOS)mobile communication environments is presented.The MIMO channel model,called for brevity C-model,captures the propagation effects that occur when vehicles move towards a junction with a side road and corner scatterings,in which both single and double bounce scattering mechanisms are assumed.The starting point for the derivation of the stochastic reference C-model is a new geometric annular intersection scattering model,where the scatterers are uniformly distributed in the form of narrow arcs on a two-dimensional(2D)plane outside the annular road.Our geometry-based channel model takes into account the exact relationship between the AOA and the AOD.The statistical properties of the C-model are studied under the assumption of non-isotropic scattering.An analytical solution is provided for the space-time-frequency cross-correlation function(STF-CCF)from which several other important characteristic quantities like the temporal auto-correlation function(ACF)can directly be obtained.The characteristics of Doppler Power Spectral Density and MIMO channel capacity as well as the influence of model parameters and scattering distribution on the performance of V2V communication system are also analyzed.The achieved theoretical results are illustrated for a typical C-junction propagation scenario.This research work provides designers of MIMO V2V communication systems an important tool in form of a wide-band spatial channel model enabling the performance analysis of new high data rate transmission schemes under propagation conditions occurring at C-junctions.Finally,based on the above dense scenarios in future 5G vehicular mobile communication environments,a 3D spherical vehicle massive MIMO antenna array model is proposed.A 3D spherical assumption is used in the proposed model instead of the 2D plane wave-front assumption in the traditional MIMO channel model.The auto-correlation properties of 3D spatial arrays are studied.Results show that the proposed 3D channel model is in close agreement with previously reported results,thereby validating the feasibility for describing channel characteristics of V2V mobile communication environments.It also provides a good theoretical reference for further analysis and discussion of the MIMO multi-path channel or 5G M-MIMO channel characteristics.