The dominant error source of mobile terminal location in wireless sensor networks (WSNs) is the non-line-of-sight (NLOS) propagation error. Among the algorithms proposed to mitigate the influence of NLOS propagati...The dominant error source of mobile terminal location in wireless sensor networks (WSNs) is the non-line-of-sight (NLOS) propagation error. Among the algorithms proposed to mitigate the influence of NLOS propagation error, residual test (RT) is an efficient one, however with high computational complexity (CC). An improved algorithm that memorizes the light of sight (LOS) range measurements (RMs) identified memorize LOS range measurements identified residual test (MLSI-RT) is presented in this paper to address this problem. The MLSI-RT is based on the assumption that when all RMs are from LOS propagations, the normalized residual follows the central Chi-Square distribution while for NLOS cases it is non-central. This study can reduce the CC by more than 90%.展开更多
This article proposes a new inner attitude integration algorithm to improve attitude accuracy of the strapdown inertial attitude and heading reference system (SIAHRS) , which, by means of a Kalman filter, integrates...This article proposes a new inner attitude integration algorithm to improve attitude accuracy of the strapdown inertial attitude and heading reference system (SIAHRS) , which, by means of a Kalman filter, integrates the calculated attitude from the accelerometers in inertial measuring unit (IMU) , called damping attitudes, with those from the conventional IMU. As vehicle' s acceleration could produce damping attitude errors, the horizontal outputs from accelerometers are firstly used to judge the vehicle' s motion so as to determine whether the damping attitudes could be reasonably applied. This article also analyzes the limitation of this approach. Furthermore, it suggests a residual chi-square test to judge the validity of damping attitude measurement in real time, and accordingly puts forward proper information fusion strategy. Finally,the effectiveness of the proposed algorithm is proved through the experiments on a real system in dynamic and static states.展开更多
基金supported by the State Key Program of National Natural Science of China (Grant No.60532030)the New Century Excellent Talents in University (Grant No.NCET-08-0333)the Natural Science Foundation of Shandong Province (Grant No.Y2007G10)
文摘The dominant error source of mobile terminal location in wireless sensor networks (WSNs) is the non-line-of-sight (NLOS) propagation error. Among the algorithms proposed to mitigate the influence of NLOS propagation error, residual test (RT) is an efficient one, however with high computational complexity (CC). An improved algorithm that memorizes the light of sight (LOS) range measurements (RMs) identified memorize LOS range measurements identified residual test (MLSI-RT) is presented in this paper to address this problem. The MLSI-RT is based on the assumption that when all RMs are from LOS propagations, the normalized residual follows the central Chi-Square distribution while for NLOS cases it is non-central. This study can reduce the CC by more than 90%.
基金Aeronautical Science Foundation of China(20080852011,20070852009)
文摘This article proposes a new inner attitude integration algorithm to improve attitude accuracy of the strapdown inertial attitude and heading reference system (SIAHRS) , which, by means of a Kalman filter, integrates the calculated attitude from the accelerometers in inertial measuring unit (IMU) , called damping attitudes, with those from the conventional IMU. As vehicle' s acceleration could produce damping attitude errors, the horizontal outputs from accelerometers are firstly used to judge the vehicle' s motion so as to determine whether the damping attitudes could be reasonably applied. This article also analyzes the limitation of this approach. Furthermore, it suggests a residual chi-square test to judge the validity of damping attitude measurement in real time, and accordingly puts forward proper information fusion strategy. Finally,the effectiveness of the proposed algorithm is proved through the experiments on a real system in dynamic and static states.