测距仪(Distance Measuring Equipment,DME)/伏尔(Very High Frequency Omnidirectional Range,VOR)/捷联惯导系统(Strap-down Inertial Navigation System,SINS)的组合是实现区域导航的重要导航源,国内针对其开展的理论研究未考虑VOR...测距仪(Distance Measuring Equipment,DME)/伏尔(Very High Frequency Omnidirectional Range,VOR)/捷联惯导系统(Strap-down Inertial Navigation System,SINS)的组合是实现区域导航的重要导航源,国内针对其开展的理论研究未考虑VOR台站磁差的影响;此外,当飞机飞行至台站上空附近时,方位测量中的野值将导致组合导航精度迅速恶化。针对上述问题,提出了一种改进的DME/VOR/SINS组合导航算法。首先,在建立状态空间模型过程中将磁差扩维进状态变量,以解决已有研究中存在的理论缺陷;其次,推导了DME斜距测量误差与位置误差间的数学关系,结合方位误差量测方程,建立卡尔曼滤波的量测方程;最后,采用一种鲁棒的基于M估计的卡尔曼滤波算法实现信息融合。测试结果表明,所设计的DME/VOR/SINS组合导航算法可以准确地估计出VOR台站磁差,显著提高了组合导航精度和算法的适用性;能有效应对方位测量值中的野值,具备较高的工程应用价值。展开更多
A hybrid method combining finite difference time domain(FDTD)with topology network was presented to treat with electromagnetic couplings and transmissions in large spaces A generalized matrix euqation expressing th...A hybrid method combining finite difference time domain(FDTD)with topology network was presented to treat with electromagnetic couplings and transmissions in large spaces A generalized matrix euqation expressing the relations among wave vectors at every port of the network nodes was give Scattering characteristics and electromagnetic distributions of every node was calculated independently using FDTD A structure of irises in a waveguide was taken as numerical examples This hybrid method has more advantages than the traditional FDTD method which includes saving calculation time,saving memory spaces and being flexible in setting up FDTD grids展开更多
文摘测距仪(Distance Measuring Equipment,DME)/伏尔(Very High Frequency Omnidirectional Range,VOR)/捷联惯导系统(Strap-down Inertial Navigation System,SINS)的组合是实现区域导航的重要导航源,国内针对其开展的理论研究未考虑VOR台站磁差的影响;此外,当飞机飞行至台站上空附近时,方位测量中的野值将导致组合导航精度迅速恶化。针对上述问题,提出了一种改进的DME/VOR/SINS组合导航算法。首先,在建立状态空间模型过程中将磁差扩维进状态变量,以解决已有研究中存在的理论缺陷;其次,推导了DME斜距测量误差与位置误差间的数学关系,结合方位误差量测方程,建立卡尔曼滤波的量测方程;最后,采用一种鲁棒的基于M估计的卡尔曼滤波算法实现信息融合。测试结果表明,所设计的DME/VOR/SINS组合导航算法可以准确地估计出VOR台站磁差,显著提高了组合导航精度和算法的适用性;能有效应对方位测量值中的野值,具备较高的工程应用价值。
基金supported by the National Natural Science Foundation of China(21002006,20452002)Special Program for Key Basic Research of the Ministry of Science and Technology,China(2004-973-36)~~
文摘A hybrid method combining finite difference time domain(FDTD)with topology network was presented to treat with electromagnetic couplings and transmissions in large spaces A generalized matrix euqation expressing the relations among wave vectors at every port of the network nodes was give Scattering characteristics and electromagnetic distributions of every node was calculated independently using FDTD A structure of irises in a waveguide was taken as numerical examples This hybrid method has more advantages than the traditional FDTD method which includes saving calculation time,saving memory spaces and being flexible in setting up FDTD grids
