主要关注利用Crossbow公司开发的Stargate网关做双层网络中的领导节点层的应用程序开发.基于到达时间偏差(Time Difference Of Arrival,TDOA)的定位技术对于传感器网络应用的有效性有着关键的作用.本文主要利用节点已采集的测距数据,在S...主要关注利用Crossbow公司开发的Stargate网关做双层网络中的领导节点层的应用程序开发.基于到达时间偏差(Time Difference Of Arrival,TDOA)的定位技术对于传感器网络应用的有效性有着关键的作用.本文主要利用节点已采集的测距数据,在Stargate上应用拉依达准则剔除粗大误差并实现基于中值绝对偏差的滤波程序开发.最后在PC机上运用Matlab分析滤波的效果如何,以及分析产生误差的原因.展开更多
According to the biased angles provided by the bistatic sensors, the necessary condition of observability and Cramer-Rao low bounds for the bistatic system are derived and analyzed, respectively. Additionally, a dual ...According to the biased angles provided by the bistatic sensors, the necessary condition of observability and Cramer-Rao low bounds for the bistatic system are derived and analyzed, respectively. Additionally, a dual Kalman filter method is presented with the purpose of eliminating the effect of biased angles on the state variable estimation. Finally, Monte-Carlo simulations are conducted in the observable scenario. Simulation results show that the proposed theory holds true, and the dual Kalman filter method can estimate state variable and biased angles simultaneously. Furthermore, the estimated results can achieve their Cramer-Rao tow bounds.展开更多
Geomagnetic orbit determination fits for nanosatellites which pursue low cost and high-density ratio,but one of its disadvantages is the poor position accuracy introduced by magnetic bias.Here,a new method,named the f...Geomagnetic orbit determination fits for nanosatellites which pursue low cost and high-density ratio,but one of its disadvantages is the poor position accuracy introduced by magnetic bias.Here,a new method,named the fuzzy regulating unscented Kalman filter(FRUKF),is proposed.The magnetic bias is regarded as a random walk model,and a fuzzy regulator is designed to estimate the magnetic bias more accurately.The input of the regulator is the derivative of magnetic bias estimated from unscented Kalman filter(UKF).According to the fuzzy rule,the process noise covariance is adaptively determined.The FRUKF is evaluated using the real-flight data of the SWARMA.The experimental results show that the root-mean-square(RMS)position error is 3.1 km and the convergence time is shorter than the traditional way.展开更多
文摘主要关注利用Crossbow公司开发的Stargate网关做双层网络中的领导节点层的应用程序开发.基于到达时间偏差(Time Difference Of Arrival,TDOA)的定位技术对于传感器网络应用的有效性有着关键的作用.本文主要利用节点已采集的测距数据,在Stargate上应用拉依达准则剔除粗大误差并实现基于中值绝对偏差的滤波程序开发.最后在PC机上运用Matlab分析滤波的效果如何,以及分析产生误差的原因.
基金the Natural Science Foundation of Jiangsu Province, China (BK2004132).
文摘According to the biased angles provided by the bistatic sensors, the necessary condition of observability and Cramer-Rao low bounds for the bistatic system are derived and analyzed, respectively. Additionally, a dual Kalman filter method is presented with the purpose of eliminating the effect of biased angles on the state variable estimation. Finally, Monte-Carlo simulations are conducted in the observable scenario. Simulation results show that the proposed theory holds true, and the dual Kalman filter method can estimate state variable and biased angles simultaneously. Furthermore, the estimated results can achieve their Cramer-Rao tow bounds.
基金supported by the National Natural Science Foundation of China(No.61673212).
文摘Geomagnetic orbit determination fits for nanosatellites which pursue low cost and high-density ratio,but one of its disadvantages is the poor position accuracy introduced by magnetic bias.Here,a new method,named the fuzzy regulating unscented Kalman filter(FRUKF),is proposed.The magnetic bias is regarded as a random walk model,and a fuzzy regulator is designed to estimate the magnetic bias more accurately.The input of the regulator is the derivative of magnetic bias estimated from unscented Kalman filter(UKF).According to the fuzzy rule,the process noise covariance is adaptively determined.The FRUKF is evaluated using the real-flight data of the SWARMA.The experimental results show that the root-mean-square(RMS)position error is 3.1 km and the convergence time is shorter than the traditional way.