Research On Intelligent Reflecting Surface Assisted Communication Technology Of Vehicle Networks

With the development of transportation system and mobile internet,the data consumption of vehicular communication networks increases rapidly.The demand for data flow and highspeed data services from vehicle mobile users is also increasing.As a key research scenario in the fifth generation(5G)of mobile communication technology,the Internet of Vehicles(Io V)has attracted the attention of researchers,telecom operators and communication companies all over the world.Intelligent reflecting surface(IRS)is a promising new technology,which can extend signal coverage through passive beamforming and achieve green communication by reducing energy loss.The main research work of this paper includes the following two aspects.Firstly,the outage performance of the the IRS-assisted Io V communication system is studied.To begin with,the overall system is modeled and the research scenarios are divided into quasi-static and moving dynamic situations.Then,for the quasi-static scenario,taylor series expansion and central limit theorem are adopted for the derivation of outage probability.Afterwards,for the moving dynamic scenario,the Doppler Effect is considered and the expression of the outage probability is derived based on numerical integration.Simulation results show that the derived expression of the outage probability is accurate.At the same time,IRS can improve the coverage and outage performance of vehicular communication networks and the Doppler Effect will cause deterioration of performance.Secondly,the estimation and compensation algorithms for doppler frequency and the channel estimation algorithm of the communication system are designed in this paper.First of all,doppler estimation algorithm for the direct channel and the reflecting channel is proposed based on turning on and off the IRS.Then,the channel estimation algorithm for the reflecting channel is studied with compressed sensing.After that,the doppler compensation algorithm is designed based on the technical feature of IRS.Simulation results show that Doppler estimation and compensation algorithms designed in this paper have high accuracy and feasibility,and the performance of the the channel estimation algorithm is close to that of the maximum likelihood estimation.IRS is of great potential to Io V communication system and it could be widely applied to practical Io V communication scenarios in the future.