共查询到17条相似文献,搜索用时 250 毫秒
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针对光纤陀螺输出信号的噪声,提出了一种处理该噪声的前向线性预测滤波与小波变换相结合的级联滤波方法,以前向线性预测滤波作为前段滤波器,采用DB4小波函数的强制阈值小波变换作为第二级滤波器。运用Allan方差法对级联滤波结果进行了分析,结果表明该级联滤波能取得较好的光纤陀螺信号降噪效果。 相似文献
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作为新一代的光学陀螺仪,光纤陀螺的性能决定着惯性参考系统的精度,为了提高光纤陀螺的精度,详细分析了陀螺随机漂移的统计特性,对实际采集的捷联陀螺漂移信号进行了分析、建模,同时采用kalman滤波,对陀螺随机漂移进行了补偿仿真,结果表明用ARMA模型描述陀螺随机漂移是合适的。 相似文献
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光纤陀螺寻北仪原理及其应用 总被引:3,自引:0,他引:3
陀螺寻北仪作为一种定北装置,在军事和民用定向中应用愈来愈多。此文介绍了一种新型陀螺寻北仪——光纤陀螺仪。在对光纤陀螺仪作了简单介绍的基础上,阐述了光纤陀螺寻北仪的原理及其应用。 相似文献
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讨论了基于方位捷联平台的陀螺寻北方案,与传统的捷联式平台不同,方位捷联平台仿真了当地的水平坐标系,并且平台的方位就是载体的方位。通过双位置方法准确计算出载体的方位角,并且抵消了陀螺的常值漂移对寻北精度的影响。分析了平台角误差和转位误差对寻北解算精度的影响。实践证明:此种方法成本低,操作方便,精度较高。 相似文献
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针对光纤测试组件信号输出特点,设计一种基于DSP的光纤惯性测试组件的数据采集系统,实现对光纤陀螺和加速度计输出信息、温度信息的A/D转换、采集、存储。针对光纤陀螺输出、温度以及加速度计输出等脉冲形式的信号,设计基于CPLD的脉冲信号计数电路,实现了固定时间间隔内的数据采样。针对加速度计温度输出为模拟信号的特点,基于24位的AD7738转换芯片通过DSP编程实现对加速度计温度信号AD转换和采集。设计了DSP与CPLD、上位机的外围通讯电路,通过对DSP内部存储器的编程,实现了对光纤惯性测试组件各信息的采集与测试,并将其发送给上位机进行存储、分析等处理。 相似文献
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为了提高船舶运动极短期预报精度及预报时间长度,本文采用小波多分辨率分析方法,将含有噪声的船舶运动信号进行了多尺度小波变换,通过采用阈值函数法对各尺度下细节信号的小波系数进行处理,对小波分解层数、小波基函数、阈值处理方法进行了深入研究,并通过模型试验数据对滤波效果进行了验证分析,实现了船舶运动信号的小波滤波.进一步针对船舶运动的非线性特性,基于深度神经网络的非线性映射能力,建立了基于LSTM网络的多步直接映射船舶运动极短期预报模型,并采用滤波后的船舶运动数据进行了不同工况下的预报分析.结果表明,不同时间长度的预报与试验结果幅值和相位吻合较好,验证了所建立的极短期预报模型的可行性. 相似文献
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LUShu-ping YANGXue-jing ZHAOXi-ren 《船舶与海洋工程学报》2004,3(1):20-23
As there are lots of non-linear systems in the real engineering, it is very important to do more researches on the modeling and prediction of non-llnear systems. Based on the muhi-resolution analysis (MRA) of wavelet theory, this paper combined the wavelet theory with neural network and established a MRA wavelet network with the scaling function and wavelet function as its neurons. From the analysis in the frequency domain, the results indicated that MRA wavelet network was better than other wavelet networks in the ability of approaching to the signals. An essential research was carried out on modeling and prediction with MRA wavelet network in the non-linear system. Using the lengthwise sway data received from the experiment of ship model, a model of offline prediction was estab lished and was applied to the short-time prediction of ship motion. The simulation results indicated that the forecasting model improved the prediction precision effectively, lengthened the forecasting time and had a better prediction results than that of AR linear model. The research indicates that it is feasible to use the MRA wavelet network in the short -time prediction of ship motion. 相似文献
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LIDi LIXu-you SUNYao 《船舶与海洋工程学报》2004,3(1):37-40
In the strapdown inertial navigation system, the Fiber Optical Gyro(FOG) must have high precision to give accurate navigation information. In this paper, a digital closed loop detection method based on the ramp wave modulating technigue is introduced. DSP and FPGA have many advantages in digital signal processing. In the design, by using DSP,a complex arithmetic operation is completed to meet the needs of closed loop control of FOG within a short time. All kinds of control signals are produced easily by FPGA, under which DSP could work properly. Combining the DSP and FPGA,the detecting method is implemented successfully. In the end, the result of test and performance is given. From the result we can conclude that the precision of FOG is improved and the noises are limited to a low level. 相似文献
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小波变换具有优良的时频分析特性,适合于提取齿轮箱等机械设备的故障特征。但是由于小波滤波器的频响应特性不理想,因此直接对信号进行小波变换会产生一定的虚假频率,从而影响故障特征提取的准确性。针对小波分析的混频现象,在深入分析该现象产生原因的基础之上提出一种改进算法,并给出了利用该算法提取故障特征的具体步骤,为舰炮齿轮箱故障特征提取提供了一个新途径。仿真结果表明,该方法能有效地消除混频现象,提高了故障特征提取的准确性。 相似文献