Research On M2M MIMO Wideband Radio Channel Models And Characteristics

Mobile-to-mobile(M2M)channel modeling is a key technology in the fourth and fifth generation communication systems,channel models are essential in assessment of their physical layer transmission technologies,in the link and system level simulations as well as in system design.M2 M communications play an important role in mobile ad hoc networks,mobile relay-based cellular networks and intelligent transportation systems.The deployment of multiple antennas at both of the transmitter(Tx)and receiver(Rx)enables the so-called Multiple-Input Multiple-Output(MIMO)technology to greatly improve the link reliability and increase the overall system capacity.In M2 M communication systems,both the Tx and Rx are in motion and equipped with low elevation antennas,which is different from conventional Fixed-to-Mobile(F2M)cellular systems where only one terminal is in motion.Moreover,most of the availbale research on M2 M radio channels is on narrowband,and there is not much work related to wideband channel characteristics.Therefore,this thesis is devoted to modeling and simulating MIMO wideband channels for M2 M communication systems.The proposed channel modeling and implementation methods are important in link and system-level simulations as well as performance evaluation of new tansmission technologies and system design for wireless M2 M MIMO wideband communication systems.In this theis,the geometry-based stochastic modeling approach is used because of its convenience for theoretical analysis and mathematical tractability.The thesis develops geometry-based stochastic scattering models in a unified coordination system,and most of the proposed models are relevant to the array responses,delay,Doppler shift,Angle-of-Departure(Ao D),Angle-of-Arrival(Ao A)and so on.By using the geometrical channel models and the channel parameters in different scenarios,the M2 M MIMO channels are realized.The channel models are further modified by comparisons between the simulated and available theoretical results or measurement results.The main contents and research contributions are summarized as follows:(1)A geometrical two-ring stochastic scattering model for M2 M MIMO wideband fading channels is proposed.The corresponding channel reference and simulation models are derived,and the channel simulation is realized by constructing channel matrix.By using the realized channel matrix,the wideband channel is further investigated by the Power-Delay-Profile(PDP)and its large scale channel parameters such as rms delay spread and so on.(2)Based on the geometrical two-ring model,a M2 M MIMO wideband channel model based on the multi-rings and multi-ellipses is proposed with 2D cross-polarized antennas at the tranceiver,which is more accurate and universal than other two-dimensional(2D)geometry-based stochastic scattering models.Based on the proposed model and realized channel,the channel parameters and characteristics at 2 and 5 GHz with 100 MHz bandwidth of Line-of-Sigh(LOS)and Non-Line-of-Sight(NLOS)scenarios are investigated and analyzed.(3)A non-stationary geometry-based street scattering model for V2 V MIMO wideband fading channels is proposed.It is assumed that static scatterers on the both roadsides are uniformly distributed in time-varying ellipses,and the mobile scatterers are uniformly distributed in time-varying segments of the road.Moreover,the number of static scatterers and moving scatterers varies with the environment.Both the relatively low-and high-speed mobile scatterers are taken into consideration to compare the case that only static scatterers exist.(4)A geometry-based stochastic scattering model for M2 M MIMO wideband channels based on Three-Dimensional(3D)two cylinders is proposed,in which we extend the narrowband model to wideband and also introduce the carrier frequency and bandwidth into the model.The channel properties and parameters are further investigated based on the simulation model and realized channels.The simulation results are compared with the 2D two-ring model as well.(5)A Geometry-Based Stochastic Scattering Model(GBSSM)based on 3D two cylinders and 2D multi-rings for M2 M MIMO wideband channels is proposed.The proposed GBSSM with 3D cross-polarized antennas combines a 3D two cylinders to model the stationary scatterers and 2D multi-rings to model the moving scatterers.The time-varying channel properties and parameters are investigated in detail for non-stationary V2 V channels.(6)A 3D geometry-based stochastic scattering model for V2 V MIMO wideband relay-based fading channel based on geometrical three cylinders is proposed.NLOS propagation condition is assumed in Amplify-and-Forward(AF)cooperative networks,where the communication from source mobile station to destination mobile station is via a mobile relay.In this work,M2 M wideband channel characteristics and signal amplitude distributions in the relay-based cooperative network are analyzed for the first time.(7)2D and 3D V2 V propagation channel models in the presence of moving scatterers are proposed.Single-Bounce Transmit(SBT),Single-Bounce Receive(SBR)and Double-Bounced(DB)components impinged on moving scatterers are considered.The complex channel gains of the proposed 2D and 3D V2 V channel models are derived,and the corresponding Auto-Correlation Function(ACF)and Doppler Power Spectral Density(D-PSD)are derived and analysed.