To improve the positioning accuracy in GPS point positioning, the geometric dilution of precision (GDOP) including HDOP, VDOP, TDOP, PDOP is commonly considered. The properties of the DOP for the GPS satellite navig...To improve the positioning accuracy in GPS point positioning, the geometric dilution of precision (GDOP) including HDOP, VDOP, TDOP, PDOP is commonly considered. The properties of the DOP for the GPS satellite navigation system are studied and the coordinate system is improved in order to decrease the amount of variables. In the end, by simulation and discussing the results, the corresponding conclusions are presented.展开更多
为了明确测距定位系统中锚点位置分布对未知点定位精度的影响情况,通过理论分析和模拟试验的方法对二维测距定位系统的几何精度因子(geometric dilution of precision,GDOP)进行分析,给出GDOP的计算方法和与GDOP值相关联的直观物理意义...为了明确测距定位系统中锚点位置分布对未知点定位精度的影响情况,通过理论分析和模拟试验的方法对二维测距定位系统的几何精度因子(geometric dilution of precision,GDOP)进行分析,给出GDOP的计算方法和与GDOP值相关联的直观物理意义。分析认为,在二维测距定位系统中,当锚点的数量N一定时,GDOP仅与从未知点到锚点的单位向量有关,且GDOP值的平方与未知点到锚点的单位向量所构成的所有三角形面积的平方和成反比。在设计定位系统时,GDOP的值越小,系统的定位精度越高。展开更多
When multiple ground-based radars(GB-rads)are utilized together to resolve three-dimensional(3-D)deformations,the resolving accuracy is related with the measurement geometry constructed by these radars.This paper focu...When multiple ground-based radars(GB-rads)are utilized together to resolve three-dimensional(3-D)deformations,the resolving accuracy is related with the measurement geometry constructed by these radars.This paper focuses on constrained geometry analysis to resolve 3-D deformations from three GB-rads.The geometric dilution of precision(GDOP)is utilized to evaluate 3-D deformation accuracy of a single target,and its theoretical equation is derived by building a simplified 3-D coordinate system.Then for a 3-D scene,its optimal accuracy problem is converted into determining the minimum value of an objective function with a boundary constraint.The genetic algorithm is utilized to solve this constrained optimization problem.Numerical simulations are made to validate the correctness of the theoretical analysis results.展开更多
根据GPS多星测距定位原理,提出在地面使用多个测站对空间飞行器进行多站测距定位,在分析其定位原理的基础上,进行定位解算的数学推导,给出几何衰减因子(Geometric Dilution Of Precision, GDOP)的理论公式,最后根据GDOP进行理论仿真,同...根据GPS多星测距定位原理,提出在地面使用多个测站对空间飞行器进行多站测距定位,在分析其定位原理的基础上,进行定位解算的数学推导,给出几何衰减因子(Geometric Dilution Of Precision, GDOP)的理论公式,最后根据GDOP进行理论仿真,同时给出结论。结论认为,在三站测距定位时,GDOP最佳值为1.732;对于近地空间飞行器(高度在1000km以下),测站间地心角应在30°~60°较好,且测站布局应接近于正三角形;若能增加测站,同时改善测站的几何布局(接近于正多边形时),可以获得更好的定位效果。展开更多
针对现有基于测距的集群UAV协同导航方法普遍忽略了空间构型对定位定能的影响,难以获得精确的导航定位结果,提出一种基于空间构型优选的5G集群UAV协同导航方法。构建了复杂环境下基于5G信号的UAV相对测距误差模型,基于最小几何精度因子(...针对现有基于测距的集群UAV协同导航方法普遍忽略了空间构型对定位定能的影响,难以获得精确的导航定位结果,提出一种基于空间构型优选的5G集群UAV协同导航方法。构建了复杂环境下基于5G信号的UAV相对测距误差模型,基于最小几何精度因子(geometric dilution of precision,GDOP)准则建立了协同导航节点寻优策略,实现了协同导航空间构型的实时优选;设计了基于5G测距网络的协同导航滤波器,对UAV导航信息进行在线估计和实时补偿,提高集群UAV的协同定位精度。仿真结果表明:该方法从机定位精度平均提升了约42.05%,为集群UAV实现在卫星不可用条件下的自主导航提供了一种有效的新方法。展开更多
基金a grant from Science and Technology Commission of Shanghai Municipality (05dz15006)
文摘To improve the positioning accuracy in GPS point positioning, the geometric dilution of precision (GDOP) including HDOP, VDOP, TDOP, PDOP is commonly considered. The properties of the DOP for the GPS satellite navigation system are studied and the coordinate system is improved in order to decrease the amount of variables. In the end, by simulation and discussing the results, the corresponding conclusions are presented.
文摘为了明确测距定位系统中锚点位置分布对未知点定位精度的影响情况,通过理论分析和模拟试验的方法对二维测距定位系统的几何精度因子(geometric dilution of precision,GDOP)进行分析,给出GDOP的计算方法和与GDOP值相关联的直观物理意义。分析认为,在二维测距定位系统中,当锚点的数量N一定时,GDOP仅与从未知点到锚点的单位向量有关,且GDOP值的平方与未知点到锚点的单位向量所构成的所有三角形面积的平方和成反比。在设计定位系统时,GDOP的值越小,系统的定位精度越高。
基金supported by the National Natural Science Foundation of China(61960206009,61971037,31727901)the Natural Science Foundation of Chongqing+1 种基金China(2020jcyj-jq X0008)Chongqing Key Laboratory of Geological Environment Monitoring and Disaster Early-warning in Three Gorges Reservoir Area(ZD2020A0101)。
文摘When multiple ground-based radars(GB-rads)are utilized together to resolve three-dimensional(3-D)deformations,the resolving accuracy is related with the measurement geometry constructed by these radars.This paper focuses on constrained geometry analysis to resolve 3-D deformations from three GB-rads.The geometric dilution of precision(GDOP)is utilized to evaluate 3-D deformation accuracy of a single target,and its theoretical equation is derived by building a simplified 3-D coordinate system.Then for a 3-D scene,its optimal accuracy problem is converted into determining the minimum value of an objective function with a boundary constraint.The genetic algorithm is utilized to solve this constrained optimization problem.Numerical simulations are made to validate the correctness of the theoretical analysis results.
文摘根据GPS多星测距定位原理,提出在地面使用多个测站对空间飞行器进行多站测距定位,在分析其定位原理的基础上,进行定位解算的数学推导,给出几何衰减因子(Geometric Dilution Of Precision, GDOP)的理论公式,最后根据GDOP进行理论仿真,同时给出结论。结论认为,在三站测距定位时,GDOP最佳值为1.732;对于近地空间飞行器(高度在1000km以下),测站间地心角应在30°~60°较好,且测站布局应接近于正三角形;若能增加测站,同时改善测站的几何布局(接近于正多边形时),可以获得更好的定位效果。
文摘针对现有基于测距的集群UAV协同导航方法普遍忽略了空间构型对定位定能的影响,难以获得精确的导航定位结果,提出一种基于空间构型优选的5G集群UAV协同导航方法。构建了复杂环境下基于5G信号的UAV相对测距误差模型,基于最小几何精度因子(geometric dilution of precision,GDOP)准则建立了协同导航节点寻优策略,实现了协同导航空间构型的实时优选;设计了基于5G测距网络的协同导航滤波器,对UAV导航信息进行在线估计和实时补偿,提高集群UAV的协同定位精度。仿真结果表明:该方法从机定位精度平均提升了约42.05%,为集群UAV实现在卫星不可用条件下的自主导航提供了一种有效的新方法。