Owing to the lack of information about geomagnetic anomaly fields,conventional geomagnetic matching algorithms in near space are prone to divergence.Therefore,geomagnetic matching navigation algorithms for hypersonic ...Owing to the lack of information about geomagnetic anomaly fields,conventional geomagnetic matching algorithms in near space are prone to divergence.Therefore,geomagnetic matching navigation algorithms for hypersonic vehicles are also prone to divergence or mismatch.To address this problem,we propose a multi-geomagnetic-component assisted localization(MCAL)algorithm to improve positioning accuracy using only the information of the main geomagnetic field.First,the main components of the geomagnetic field and a mathematical representation of the Earth’s geomagnetic field(World Magnetic Model 2015)are introduced.The mathematical relationships between the geomagnetic components are given,and the source of geomagnetic matching error is explained.We then propose the MCAL algorithm.The algorithm uses the intersections of the isopleths of the geomagnetic components and a decision method to estimate the real position of a carrier with high positioning accuracy.Finally,inertial/geomagnetic integrated navigation is simulated for hypersonic boost-glide vehicles.The simulation results demonstrate that the proposed algorithm can provide higher positioning accuracy than conventional geomagnetic matching algorithms.When the random error range is±30 nT,the average absolute latitude error and longitude error of the MCAL algorithm are 151 m and 511 m lower,respectively,than those of the Sandia inertial magnetic aided navigation(SIMAN)algorithm.展开更多
This paper analyzes the distribution characteristics of geomagnetic low-value displacement in Gansu and its adjacent areas from 1995 to 2003 on the basis of the data of the daily amplitude minimum value time of the ge...This paper analyzes the distribution characteristics of geomagnetic low-value displacement in Gansu and its adjacent areas from 1995 to 2003 on the basis of the data of the daily amplitude minimum value time of the geomagnetic vertical component. It is shown that in addition to the changing rules of geomagnetic low-value displacement itself, there is a better correlation between geomagnetic low-value displacement and the occurrence of moderately strong earthquakes. There appeared to be geomagnetic low-value displacement before the moderately strong earthquakes in Gansu in the 9 years from 1995 to 2003. This result indicates that geomagnetic low-value displacement is of instructive significance for earthquake prediction to some extents.展开更多
基金Project supported by the Space Science and Technology Innovation Fund of China(No.2016KC020028)the Fund of China Space Science and Technology(No.2017-HT-XG)。
文摘Owing to the lack of information about geomagnetic anomaly fields,conventional geomagnetic matching algorithms in near space are prone to divergence.Therefore,geomagnetic matching navigation algorithms for hypersonic vehicles are also prone to divergence or mismatch.To address this problem,we propose a multi-geomagnetic-component assisted localization(MCAL)algorithm to improve positioning accuracy using only the information of the main geomagnetic field.First,the main components of the geomagnetic field and a mathematical representation of the Earth’s geomagnetic field(World Magnetic Model 2015)are introduced.The mathematical relationships between the geomagnetic components are given,and the source of geomagnetic matching error is explained.We then propose the MCAL algorithm.The algorithm uses the intersections of the isopleths of the geomagnetic components and a decision method to estimate the real position of a carrier with high positioning accuracy.Finally,inertial/geomagnetic integrated navigation is simulated for hypersonic boost-glide vehicles.The simulation results demonstrate that the proposed algorithm can provide higher positioning accuracy than conventional geomagnetic matching algorithms.When the random error range is±30 nT,the average absolute latitude error and longitude error of the MCAL algorithm are 151 m and 511 m lower,respectively,than those of the Sandia inertial magnetic aided navigation(SIMAN)algorithm.
基金sponsored by the Natural Science Foundation of Gansu Province (3ZS061-A25-008),China
文摘This paper analyzes the distribution characteristics of geomagnetic low-value displacement in Gansu and its adjacent areas from 1995 to 2003 on the basis of the data of the daily amplitude minimum value time of the geomagnetic vertical component. It is shown that in addition to the changing rules of geomagnetic low-value displacement itself, there is a better correlation between geomagnetic low-value displacement and the occurrence of moderately strong earthquakes. There appeared to be geomagnetic low-value displacement before the moderately strong earthquakes in Gansu in the 9 years from 1995 to 2003. This result indicates that geomagnetic low-value displacement is of instructive significance for earthquake prediction to some extents.
