捷联惯性测量组合挠性陀螺静态漂移试验标定

本文研究了捷联惯性测量组合中挠性陀螺静态漂移模型系数的标定问题。对捷联惯性测量组合中挠性陀螺静态漂移误差进行了建模，研究了采用多位置试验对陀螺静态漂移模型系数进行标定的方法。探讨了采用位置试验对捷联惯性测量组合挠性陀螺静态漂移系数可靠地进行标定所需选取的最少位置数，试验证明了用最少位置实验进行标定的有效性。     

导航、制导设备与导航台

0102680时间和频率在广域增强系统中的作用[刊]/戴琰//空间电子技术.—2000,(3).—41～46(E)0102681捷联惯性测量组合标定的仿真研究[刊]/张卫东//压电与声光.—2000,22(5).—348～352(L)对卡尔曼滤波在捷联惯性测量组合标定中的应用进行了研究.提出了一种辨识激光陀螺和加速度计静态误差的在线正交标定方案,并在不同滤波条件下进行了仿真验证,结果表明这是一种比较有效的误差际定方法。参6     

捷联惯性测量装置全温度标定方法

为了提高捷联惯性测量装置(SIMU)的测量精度,在使用前必须对其进行标定,以确定SIMU的参数及性能指标.为此研究了一种SIMU的全温度标定方法,利用专用的测试设备对SIMU进行全温度标定试验.给出了SIMU的静态模型方程,详细介绍了模型方程中各参数的标定方法及具体的误差补偿计算方法,最后给出了SIMU综合性能指标的计算.经过多发SIMU的标定实验,结果表明:该标定方法有效地提高了SIMU的实际实用精度.     

基于 PSO 算法的加速度计快速标定方法

为减少惯性测量组合标定对转台的依赖,降低标定对转台控制精度的要求,在分析传统加速度计模观测迭代标定方法的基础上,提出一种基于粒子群优化算法（PSO）的加速度计快速标定方法。首先,基于模观测思想设计构造目标优化函数,并将其作为 PSO 算法中的适应度函数,实现了标定方法与 PSO 算法的连接;其次,设计了基于最大化观测信息相对于待估计参数的敏感度函数的加速度计标定编排方案;最后,对所提方法与牛顿迭代标定方法进行了对比仿真。仿真实验结果表明,基于 PSO 算法的加速度计快速标定方法具有可行性、有效性,与传统牛顿迭代标定方法相比更具有优越性。     

激光陀螺IMU的不水平指北标定方法

激光陀螺捷联惯组(SIMU)标定是惯性导航的前提,标定结果的好坏将对惯性导航精度产生直接的影响.根据激光惯性组合(IMU)的误差方程,在激光捷联惯性组合不水平指北情况下,通过12位置的标定方法,抵消地速及重力加速度的影响,从而得出加速度计的误差参数和激光陀螺的常值漂移;然后通过单轴转台,标定出陀螺的安装误差和标度因数.此方法可满足激光陀螺IMU的标定要求.本方案利用最少的测试位置,方法简单,得到了所有需要的信息,利用率高.     

实现惯测坐标系正交同步的系统级标定技术

文中研究目的有两个方面,一是在外场条件下实现低精度测试设备标定高精度捷联惯性导航装置;二是标定过程中实现惯性测量坐标系正交同步,进而提高捷联惯导动态导航精度。据此,文章在深入分析惯性测量坐标系空间相对关系的基础上,对惯性测量坐标系进行正交化,并通过建立正交化后惯性测量坐标系之间的失准角模型,从而完成基于惯性测量坐标系非正交角及失准角的系统级标定滤波器的构建以及系统级标定方案的设计,同时,针对外场测试设备限制文中制定了系统级标定抗扰动措施,并进行了试验验证。试验结果表明:该标定方法可以实现捷联惯导全参数系统级标定,提高系统动态环境下定位精度三倍以上。     

MEMS微惯性组合静态误差建模与补偿

安装误差和温度是MEMS微惯性组合的主要误差源,这两种因素所引起的误差通常占系统总误差的90%以上。通过对微惯性组合的安装误差及温度因素的影响进行深入分析,构建了一种适用于低成本导航微惯性组合静态误差补偿模型。该模型是一种基于线性模型的改进型模型,模型复杂度低,按实验标定方法获取模型参数后可实时计算惯组输出,用于对MEMS微惯性组合实时性要求高的环境中。并且,通过对模型深入分析,巧妙设计标定方法,大大简化了该模型的标定步骤,使模型参数的获取更为方便。为了论证模型正确性,进行了标定实验,实验结果表明模型是切实可靠的。     

弹载滚转稳定平台相对转角测量电路设计

提高常规高旋弹药飞行姿态参数测量精度的难点是如何解决惯性器件量程与精度互相矛盾的问题。采用滚转稳定平台能够解决弹体高旋对惯性器件量程的影响,能够采用小量程、高精度的陀螺仪测量弹体的飞行姿态参数。然而滚转稳定平台的惯性测量组合与弹体之间有相对转动,此时惯性测量组合所测参数并不是弹体的飞行参数,需要一个能够测量相对转角的装置才能得到弹体完整的飞行姿态参数。针对此问题,本文利用增量式光电编码器设计相对转角测量电路,并对增量式光电编码器在实际应用过程中出现的问题进行了研究,最后通过三轴飞行仿真转台试验进行验证。试验证明,该相对转角测量电路具有一定的可行性和有效性,能够有效测量惯性测量组合与弹体之间的相对转角,具有一定的工程应用价值。     

电磁环境对重力下垂参数标定的影响

在航天测量船无线电测量设备重力下垂参数标定中常常会受到电磁环境的影响,导致标定结果失真(参数值不可用)。为提高设备的跟踪精度,需获得较为准确的重力下垂参数。设电磁环境影响参数ξ,将参数ξ代入到相关的标定过程中去定量分析影响量,给出了ξ对重力下垂参数的影响量值,同时得到结论:重力下垂参数ΔEG和电磁环境影响ξ对电轴在方向上的影响相同,反向法无法分离两种误差。为分离两种误差,消除环境影响量ξ,对重力下垂参数标定的工程方法进行了改进,依据误差的包含关系,将传统的对塔方法和跟踪信标球的方法相结合,通过相关数学方法处理得到较为准确的重力下垂参数,经过试验验证,该方法可行,标定结果可信。     

基于V/F转换的自标定加速度计数据采集处理单元

自标定加速度计组合是将加速度计与标定装置有机结合的新型惯性组件,采用高精度的转位/锁紧机构,利用重力场下敏感器件多位置翻滚的方法分离出加速度计(组合)的各项模型参数.为保证其高精度,采用了基于电压-频率(V/F)转换的数据采集单元来完成加速度计信号的数字化.V/F转换器将加速度计输出的模拟信号转换为脉冲量,FPGA采集脉冲量并转换得到自标定模型所需数字量.在单片机中进行数字滤波有效地降低了数据中的噪声.实验证明,基于V/F转换的数据采集系统为自标定加速度计组合的标定解算提供了低噪声、高精度的数据,从源头上保证了自标定的高精度.     

Microcontroller susceptibility variations to EFT burst during accelerated aging

With deterioration of the electromagnetic environment, microcontroller unit (MCU) electromagnetic susceptibility (EMS) to transient burst interference has become a focus of academia and enterprise. Most electromagnetic compatibility (EMC) studies of MCUs have not taken the effects of aging into account. However, component aging can degrade the physical parameters of an MCU and change its immunity to EMI. This paper proposes a time-equivalent interval accelerated aging methodology combining DC electrical and high temperature stresses. The test results show variations in susceptibility to electrical fast transients (EFT) burst revealing increasing susceptibility. The reasons for MCU immunity drifts in the aging process are discussed.     

EMI Susceptibility Model of Signal Conditioning Circuits Based on Operational Amplifiers

Circuits based on operational amplifiers (OPAMPs) are susceptible to electromagnetic interference (EMI) in the radio-frequency range due to the AM demodulation produced by non-linearity of internal transistors. Such a phenomenon produces demodulated signals in the low-frequency range. This paper presents a model to predict the susceptibility of analog signal-conditioning circuits, based on a few test parameters, while ignoring the internal structure of OPAMPs involved in the circuit. The method has been experimentally tested in two applications: (1) test of simple instrumentation adapter circuits and (2) predictions of susceptibility of an amplifier for an electret microphone, tested according to EN55020.     

Comparison among emission and susceptibility reduction techniques for electromagnetic interference in digital integrated circuits

This paper presents a comparative study of susceptibility reduction techniques for electromagnetic interference (EMI) in digital integrated circuits (ICs). Both direct power injection (DPI) and very-fast transmission-line pulsing (VF-TLP) methods are used to inject interference into the substrate of a single test chip. This IC is built around six functionally identical cores, differing only by their EMI protection strategies (RC protection, isolated substrate, meshed power supply network) which were initially designed for low emission design rules. The ranking of three of these cores in terms of electromagnetic immunity is then compared with the one of their radiated emission, thanks to near-field scanning (NFS) measurements. This leads to the establishing of design guidelines for low EMI in digital ICs.     

CRT 显示器电磁敏感性初探

采用大电流注入（BCI）的试验方法对计算机用CRT 显示器的电磁敏感性（EMS）进行研究。试验中,将某一频率下不同幅度的连续波信号作为电磁干扰信号注入到VGA 接口的RGB、水平同步（HS）、垂直同步（VS）信号线中。当HS 信号线中注入干扰信号时,CRT 出现斜条纹这一电磁敏感现象,电磁干扰信号越强,斜条纹越明显,而RGB、VS 信号 线注入时,则没有出现上述现象。此外,还研究了注入信号与HS 信号线耦合信号的关系。     

电磁干扰滤波器的参数及其测试

EMI滤波器作为抑制电磁干扰的最有力的手段,日益为人们所了解和广泛使用。对EMI滤波器的理解、应用及测试技术的掌握就变得十分重要。文章介绍EMC常用组件,讨论常用的滤波器的分类及选择,重点介绍EMI滤波器的测试指标和标准,分析EMI滤波器的测试方法.     

Reducing the EMI Susceptibility of a Kuijk Bandgap

In this paper, the susceptibility of a Kuijk bandgap voltage reference to electromagnetic interferences (EMIs) superimposed to the power supply is investigated. A model of the bandgap circuit is derived from experimental tests consisting of scattering parameters and susceptibility measurements on a test chip. The model is able to correctly predict the susceptibility of the circuit by means of SPICE transient simulations. The simulations identify the fundamental stray components responsible for EMI coupling that are usually not taken into account in postlayout analyses. From the EMI point of view, the rectification phenomenon of bipolar transistors, used in the bandgap cell, and the operational amplifier (op-amp) input distortion are shown to cause the voltage reference performance degradation. In particular, for the first time, the importance of the bandgap cell is pointed out, suggesting that the measures to reduce the susceptibility of the op-amp may not be sufficient to guarantee the bandgap immunity. Moreover, the analyses of main parasitic paths (from the power supply net to the more sensitive nodes) demonstrate the relevance of paths that are not commonly considered during the design phase and that may lead to an immunity degradation. Possible solutions to reduce the bandgap susceptibility are also explored, suggesting design criteria, filtering techniques, and layout variations. A second test chip is designed and manufactured to validate the suggested improvements and verify the critical role of the bandgap cell. Finally, a simplified theoretical analysis, which allows a fast bandgap susceptibility evaluation, is presented. This tool is used to point out the importance of the rectification phenomenon compared to the op-amp differential pair distortion.      

A systematic coupled approach for electromagnetic susceptibility analysis of a shielded device with multilayer circuitry

This paper presents a systematic coupled approach for electromagnetic susceptibility (EMS) analysis of a shielded electronic device in the presence of an ambient electromagnetic interference (EMI). A full-wave electromagnetic modeling technique coupled with a circuit-based method is developed for the overall EMS performance analysis. The mixed-potential electric field integral equation (MPIE) is formulated via the method of moments to model the electromagnetic properties of an arbitrary structure consisting of wires and surfaces with any applied excitation. With numerical analysis, the effect of an ambient electromagnetic noise is characterized, and an equivalent circuit model is extracted for further analysis of EMI to internal high-speed sensitive circuits. Numerous examinations exhibit that this systematic coupled approach is a computationally efficient method to address the EMS problems at system level, in which the external EMI effects are fully considered and the circuit-based simulator is also exploited.     

EMI-induced failures in crystal oscillators

An electromagnetic interference (EMI) induced failure mode pertaining to crystal-based voltage-controlled oscillators (VCO) has been studied. The failure consists of a transition to a frequency of oscillation that differs from the crystal's fundamental resonant frequency, when the circuit is temporarily exposed to continuous or pulsed radio-frequency electromagnetic fields. The new state persists even after the EMI source is removed and leads to hang-up in digital systems. This mode transition has been observed experimentally. Its essential properties have been predicted theoretically and simulated numerically, using simplified oscillator models. The likelihood of observing such a failure in a noisy electromagnetic environment is assessed with respect to the radiated susceptibility levels given in MIL-STD-461B     

Failures induced on analog integrated circuits by conveyed electromagnetic interferences: A review

Failures induced on analog integrated circuits by electromagnetic interference (EMI) will be analyzed with particular emphasis on integrated operational amplifiers built with different technologies. Additionally, the correlation found between EMI susceptibility and large-signal opamp behavior will be discussed. Some criteria for the design of low EMI susceptibility opamps will be derived. Finally, as an application example, the design of a BiCMOS opamp with an extremely low-probability EMI-induced failure will be presented.     

Analysis of high-speed interconnects in the presence ofelectromagnetic interference

This paper describes an efficient algorithm based on moment-matching techniques for simulation of high-speed circuits in the presence of electromagnetic interference (EMI). The proposed method is based on the recently developed complex frequency hopping (CFH) technique for interconnect analysis. The new technique is useful for susceptibility analysis and is two to three orders of magnitude faster than conventional simulation techniques. In addition, it can be extended to the analysis of interconnects with frequency-dependent parameters and nonlinear terminations