A temperature sensor based on polarization non-reciprocity (PNR) in fiber-optic Sagnac interferometer (FSI) was proposed. The experimental study was made primarily and the results agree with theory well. Discussion sh...A temperature sensor based on polarization non-reciprocity (PNR) in fiber-optic Sagnac interferometer (FSI) was proposed. The experimental study was made primarily and the results agree with theory well. Discussion shows that this kind of temperature sensor can achieve high precision and have great application potential.展开更多
Inertial navigation represents a unique method of navigation,in which there is no dependency on external sources of information.As opposed to other position fixing navigation techniques,inertial navigation performs th...Inertial navigation represents a unique method of navigation,in which there is no dependency on external sources of information.As opposed to other position fixing navigation techniques,inertial navigation performs the navigation in a relative sense with respect to the initial navigation state of the moving platform.Hence,inertial navigation systems are not prone to jamming,or spoofing.Inertial navigation systems have developed vastly,from their occurrence in the 1940s up to date.The accuracy of the inertial sensors has improved over time,making inertial sensors sufficient in terms of size,weight,cost,and accuracy for navigation and guidance applications.Within the past few years,inertial sensors have developed from being purely mechanical into incorporating various technologies and taking advantage of numerous physical phenomena,from which the dynamic forces exerted on a moving body could be computed accurately.Besides,the evolution of inertial navigation scheme involved the evolution from stable-platform inertial navigation system,which were mechanically complicated,to computationally demanding strap-down inertial navigation systems.Optical sensory technologies have provided highly accurate inertial sensors,at smaller sizes.Besides,the vibratory inertial navigation technologies enabled the production of Micro-electro-machined inertial sensors that are extremely low-cost,and offer extremely low size,weight and power consumption,making them suitable for a wide range of day-to-day navigation applications.Recently,advanced inertial sensor technologies have been introduced to the industry such as nuclear magnetic resonance technology,coldatom technology,and the reintroduction of fluid-based inertial sensors.On another note,inertial sensor errors constitute a huge research aspect in which it is intended for inertial sensors to reach level in which they could operate for substantially long operation times in the absence of updates from aiding sensors,which would be a huge leap.Inertial sensors error modeling technique展开更多
对光纤陀螺随机噪声的ARMA建模及卡尔曼滤波方法进行了研究。针对ARMA(Auto-Regressive and Moving Average自回归滑动平均)模型的有色噪声在状态方程中不能通过传统的状态扩充法进行白化的问题,提出了新的噪声白化方法:采用增广最小二...对光纤陀螺随机噪声的ARMA建模及卡尔曼滤波方法进行了研究。针对ARMA(Auto-Regressive and Moving Average自回归滑动平均)模型的有色噪声在状态方程中不能通过传统的状态扩充法进行白化的问题,提出了新的噪声白化方法:采用增广最小二乘法估计ARMA模型的参数,同时提取出ARMA模型中的驱动白噪声,从而可以把ARMA模型中的有色噪声项作为控制项放入系统的状态方程,通过Sage-Husa的次优无偏MAP(Maximum A Posteriori,极大后验)噪声统计估值器对系统噪声的统计特性进行估计,实现了系统噪声的白化。在此基础上应用自适应卡尔曼滤波,有效消除了误差,得到状态值的准确估计。实验结果表明,对于随机噪声的自相关和互相关特性均呈现拖尾性质的光纤陀螺,采用新方法比传统基于AR模型的Kalman滤波降噪方法滤除噪声的效果提高了10%以上。展开更多
文摘A temperature sensor based on polarization non-reciprocity (PNR) in fiber-optic Sagnac interferometer (FSI) was proposed. The experimental study was made primarily and the results agree with theory well. Discussion shows that this kind of temperature sensor can achieve high precision and have great application potential.
基金Dr.Naser El-Sheimy research funds from NSERC and Canada Research Chairs programs(Grant No.RT691875).
文摘Inertial navigation represents a unique method of navigation,in which there is no dependency on external sources of information.As opposed to other position fixing navigation techniques,inertial navigation performs the navigation in a relative sense with respect to the initial navigation state of the moving platform.Hence,inertial navigation systems are not prone to jamming,or spoofing.Inertial navigation systems have developed vastly,from their occurrence in the 1940s up to date.The accuracy of the inertial sensors has improved over time,making inertial sensors sufficient in terms of size,weight,cost,and accuracy for navigation and guidance applications.Within the past few years,inertial sensors have developed from being purely mechanical into incorporating various technologies and taking advantage of numerous physical phenomena,from which the dynamic forces exerted on a moving body could be computed accurately.Besides,the evolution of inertial navigation scheme involved the evolution from stable-platform inertial navigation system,which were mechanically complicated,to computationally demanding strap-down inertial navigation systems.Optical sensory technologies have provided highly accurate inertial sensors,at smaller sizes.Besides,the vibratory inertial navigation technologies enabled the production of Micro-electro-machined inertial sensors that are extremely low-cost,and offer extremely low size,weight and power consumption,making them suitable for a wide range of day-to-day navigation applications.Recently,advanced inertial sensor technologies have been introduced to the industry such as nuclear magnetic resonance technology,coldatom technology,and the reintroduction of fluid-based inertial sensors.On another note,inertial sensor errors constitute a huge research aspect in which it is intended for inertial sensors to reach level in which they could operate for substantially long operation times in the absence of updates from aiding sensors,which would be a huge leap.Inertial sensors error modeling technique
文摘对光纤陀螺随机噪声的ARMA建模及卡尔曼滤波方法进行了研究。针对ARMA(Auto-Regressive and Moving Average自回归滑动平均)模型的有色噪声在状态方程中不能通过传统的状态扩充法进行白化的问题,提出了新的噪声白化方法:采用增广最小二乘法估计ARMA模型的参数,同时提取出ARMA模型中的驱动白噪声,从而可以把ARMA模型中的有色噪声项作为控制项放入系统的状态方程,通过Sage-Husa的次优无偏MAP(Maximum A Posteriori,极大后验)噪声统计估值器对系统噪声的统计特性进行估计,实现了系统噪声的白化。在此基础上应用自适应卡尔曼滤波,有效消除了误差,得到状态值的准确估计。实验结果表明,对于随机噪声的自相关和互相关特性均呈现拖尾性质的光纤陀螺,采用新方法比传统基于AR模型的Kalman滤波降噪方法滤除噪声的效果提高了10%以上。
