在基于时间到达差(Time Difference Of Arrival,TDOA)的定位估计算法中,CHAN算法计算量小,能够在视距(Line Of Sight,LOS)传播环境下获得较高的定位精度,因而被广泛应用。但是在非视距传播环境(Non-Line Of Sight,NLOS)下,该算法的定位...在基于时间到达差(Time Difference Of Arrival,TDOA)的定位估计算法中,CHAN算法计算量小,能够在视距(Line Of Sight,LOS)传播环境下获得较高的定位精度,因而被广泛应用。但是在非视距传播环境(Non-Line Of Sight,NLOS)下,该算法的定位性能会明显下降。因为在非视距情况,尤其是密集城区,由于建筑物等障碍物的存在使得无线电信号无法直线传播,这就引入了NLOS误差;而CHAN算法中的加权矩阵只考虑了系统误差,无法消除NLOS误差。文中在基于视距环境下CHAN算法的研究基础上,对非视距引入的NLOS误差的统计特性进行分析,给出一种在NLOS情况下,通过优化非视距TDOA测量值误差的方法来改善非视距下的CHAN算法性能,并通过仿真分析了CHAN算法在不同环境模型下的定位性能。仿真结果表明,改善的CHAN算法在NLOS环境下能取得较好的定位性能。展开更多
In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)environ...In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)environments.In the proposed sum-of-sinusoids(SoS)channel model,the waves that emerge from the transmitter undergo line-of-sight(LoS)and non-line-of-sight(NLoS)propagation to the receiver,which makes the model suitable for describing numerous V2X wireless communication scenarios for sixth-generation(6G).We derive expressions for the real and imaginary parts of the complex channel impulse response(CIR),which characterize the physical propagation characteristics of V2X wireless channels.The statistical properties of the real and imaginary parts of the complex CIRs,i.e.,autocorrelation functions(ACFs),Doppler power spectral densities(PSDs),cross-correlation functions(CCFs),and variances of ACFs and CCFs,are derived and discussed.Simulation results are generated and match those predicted by the underlying theory,demonstrating the accuracy of our derivation and analysis.The proposed framework and underlying theory arise as an efficient tool to investigate the statistical properties of 6G MIMO V2X communication systems.展开更多
This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good resul...This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good results.Firstly,an electromagnetic(EM)wave NLOS multipath propagation model for vehicle scene is established.Subsequently,with the help of available multipath echoes,a complete NLOS vehicle localiza-tion algorithm is proposed.Finally,simulation and experimental results validate the effectiveness of the established EM wave propagation model and the proposed NLOS vehicle localization algorithm.展开更多
文摘在基于时间到达差(Time Difference Of Arrival,TDOA)的定位估计算法中,CHAN算法计算量小,能够在视距(Line Of Sight,LOS)传播环境下获得较高的定位精度,因而被广泛应用。但是在非视距传播环境(Non-Line Of Sight,NLOS)下,该算法的定位性能会明显下降。因为在非视距情况,尤其是密集城区,由于建筑物等障碍物的存在使得无线电信号无法直线传播,这就引入了NLOS误差;而CHAN算法中的加权矩阵只考虑了系统误差,无法消除NLOS误差。文中在基于视距环境下CHAN算法的研究基础上,对非视距引入的NLOS误差的统计特性进行分析,给出一种在NLOS情况下,通过优化非视距TDOA测量值误差的方法来改善非视距下的CHAN算法性能,并通过仿真分析了CHAN算法在不同环境模型下的定位性能。仿真结果表明,改善的CHAN算法在NLOS环境下能取得较好的定位性能。
基金supported by National Natural Science Foundation of China(NSFC)(No.62101274 and 62101275)Natural Science Foundation of Jiangsu Province(BK20210640)Open Research Fund of National Mobile Communications Research Laboratory Southeast University under Grant 2021D03。
文摘In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)environments.In the proposed sum-of-sinusoids(SoS)channel model,the waves that emerge from the transmitter undergo line-of-sight(LoS)and non-line-of-sight(NLoS)propagation to the receiver,which makes the model suitable for describing numerous V2X wireless communication scenarios for sixth-generation(6G).We derive expressions for the real and imaginary parts of the complex channel impulse response(CIR),which characterize the physical propagation characteristics of V2X wireless channels.The statistical properties of the real and imaginary parts of the complex CIRs,i.e.,autocorrelation functions(ACFs),Doppler power spectral densities(PSDs),cross-correlation functions(CCFs),and variances of ACFs and CCFs,are derived and discussed.Simulation results are generated and match those predicted by the underlying theory,demonstrating the accuracy of our derivation and analysis.The proposed framework and underlying theory arise as an efficient tool to investigate the statistical properties of 6G MIMO V2X communication systems.
基金supported by the National Natural Science Foundation of China(62201510,62001091,61801435,61871080,61801435)the Initial Scientific Research Foundation of University of Science and Technology of China(Y030202059018051)+2 种基金Yangtze River Scholar Program,Sichuan Science and Technology Program(2019JDJQ0014)111 Project(B17008)Henan Provincial Department of Science and Technology Research Project(202102210315,212102210029,202102210-137).
文摘This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good results.Firstly,an electromagnetic(EM)wave NLOS multipath propagation model for vehicle scene is established.Subsequently,with the help of available multipath echoes,a complete NLOS vehicle localiza-tion algorithm is proposed.Finally,simulation and experimental results validate the effectiveness of the established EM wave propagation model and the proposed NLOS vehicle localization algorithm.