Although the Cramer-Rao Bound(CRB) can be used as the benchmark of estimation algorithm performance,it's too complicated for joint training sequence(TS) design for multiple input multiple output(MIMO) orthogonal f...Although the Cramer-Rao Bound(CRB) can be used as the benchmark of estimation algorithm performance,it's too complicated for joint training sequence(TS) design for multiple input multiple output(MIMO) orthogonal frequency division multiplexing(OFDM) coordination on multiple point(CoMP) systems.So a minimum mean square error(MSE) based sub-optimal sequence design criterion was proposed,including ideal sequence correlation property and sequence length constraint.The simulation results verify the theory analysis.展开更多
Urban vegetation has been an important indicator for the evaluation of eco-cities,which is of great significance to promote eco-city construction. We study and discuss the commonly used urban vegetation extraction met...Urban vegetation has been an important indicator for the evaluation of eco-cities,which is of great significance to promote eco-city construction. We study and discuss the commonly used urban vegetation extraction methods. The extraction of vegetation points in this study is completed through mathematical statistics,mean-square error,successive differences and iterative algorithm which are based on the analysis of different spatial morphological characteristics in urban point clouds. Linyi,a city of Shandong Province in China,is selected as the study area to test this method and the result shows that the proposed method has a strong practicality in urban vegetation point cloud extraction. Only 3D coordinate properties of the LiDAR point clouds are used in this method and it does not require additional information,for instance,return intensity,which makes the method more applicable and operable.展开更多
基金International Science&Technology Cooperation Projects of Qinghai,China(Nos.2013-H-811,2014-HZ-821)Chunhui Plan Projects,China(Nos.Z2014013,Z2014014)
文摘Although the Cramer-Rao Bound(CRB) can be used as the benchmark of estimation algorithm performance,it's too complicated for joint training sequence(TS) design for multiple input multiple output(MIMO) orthogonal frequency division multiplexing(OFDM) coordination on multiple point(CoMP) systems.So a minimum mean square error(MSE) based sub-optimal sequence design criterion was proposed,including ideal sequence correlation property and sequence length constraint.The simulation results verify the theory analysis.
文摘Urban vegetation has been an important indicator for the evaluation of eco-cities,which is of great significance to promote eco-city construction. We study and discuss the commonly used urban vegetation extraction methods. The extraction of vegetation points in this study is completed through mathematical statistics,mean-square error,successive differences and iterative algorithm which are based on the analysis of different spatial morphological characteristics in urban point clouds. Linyi,a city of Shandong Province in China,is selected as the study area to test this method and the result shows that the proposed method has a strong practicality in urban vegetation point cloud extraction. Only 3D coordinate properties of the LiDAR point clouds are used in this method and it does not require additional information,for instance,return intensity,which makes the method more applicable and operable.