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针对传统船摇隔离度测试方法效率低、误差大、操作复杂、且不能有效解决扰动跳变的不足,对船摇隔离的基本原理进行了分析,建立了梯度型最小二乘滤波模型,提出了基于梯度型最小二乘滤波和VC++语言编程实现船摇隔离度的自动测试方法,并利用跟踪实测数据进行了仿真实验。对比传统方法测试结果表明,该方法能有效滤除测量数据中的随机误差,较大程度地降低了扰动跳变的抖动量,提高了伺服系统船摇隔离度的测试精度。 相似文献
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分析空间激光通信移动平台角运动和框架偏转之间的速度耦合关系,给出克服移动平台角运动的视轴稳定方法,针对视轴稳定系统中存在的非线性、多干扰问题,应用自抗扰控制法对三轴视轴稳定系统进行分散独立控制,采用模糊理论对自抗扰控制器的相关参量进行自整定.仿真和模拟实验表明:在1Hz条件下,相对于参量辨识控制法,模糊自抗扰控制法的抗扰动隔离度提高了7.4dB;在模拟扫频实验条件下,将1~2Hz与2~4Hz的扰动实验区间进行比较,模糊自抗扰控制法的抗扰动隔离度下降仅2.2dB.模糊自抗扰控制具有较好的快速响应性、较小的超调和频率适应性,能够满足系统稳态准确度的要求,并能克服平台角运动耦合、不确定性扰动问题. 相似文献
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《中国光学》2020,(3)
受空间所限,激光通信地面测试平台与被测终端之间的距离远小于实际通信距离,导致测试平台光机等器件产生的后向散射杂光进入被测终端,从而严重影响被测终端的测试性能。从被测终端与测试平台间的光学干扰问题出发,本文研究了被测终端与测试平台间隔离度的关系,分别设计了卡塞格林和离轴三反光学天线,并根据杂散光传输模型,采用杂散光分析软件分析了光学天线结构形式及表面粗糙度两方面对隔离度的影响。分析结果表明,采用离轴三反光学天线时的隔离度明显高于卡塞格林光学天线,且隔离度随着光学表面粗糙度的减小而增大,当光学表面的粗糙度达到0.892 nm时,隔离度可达-86.22 dB。最后,推导了ABg模型与Harvey模型参数间的关系,并根据粗糙度与TIS计算公式,得出粗糙度分别为0.7 nm及0.5 nm的ABg模型参数,它们的终端间隔离度分别为-94.39 dB和-97.3 dB,实现了-90 dB的隔离度指标。 相似文献
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一种有效提高薄膜滤光片型密集波分复用器器件性能的方法及其实验研究 总被引:1,自引:1,他引:0
对光梳状滤波器加薄膜滤光片型模块制作密集波分复用器(DWDM)的两种应用方案进行了研究,提出了一种提高插损一致性、信道隔离度及减小串扰的结构方案。对新结构方案与常规结构方案进行了理论分析及实验研究,结果表明新结构可将级联次级峰由大于-30dB降至-50dB以下。用16波50GHz的密集波分复用器件拼接进行的实验表明最终器件的插损减小0.869dB,插损一致性减小2.005dB,相邻信道隔离度提高1.004dB,非相邻信道隔离度提高42.903dB.总串扰提高1.68dB。该方案不仅可以应用到光梳状滤波器与薄膜滤光片型模块拼接高性能的超密集波分复用器件.同样也可适用于阵列波导光栅等类型的密集波分复用器件中以降低工艺难度,提高性能指标。 相似文献
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针对二维陀螺平台方位瞄准线控制在过顶位置时因驱动轴和敏感轴存在非线性约束导致的不稳定问题,分析了不同类型扰动源对方位瞄准线稳定的影响及其随俯仰角变化的规律,提出了基于扰动源分类控制的过顶稳定方法。该方法采用反馈和前馈双通道复合控制结构,在过顶位置时基于控制结构自身消除陀螺测量噪声放大导致的内生力矩扰动,通过增加前馈通道的滤波环节,抑制横滚扰动高频分量引起的力矩扰动,解决了过顶位置时方位驱动轴震荡的问题,同时通过反馈通道和前馈通道分别实现对方位扰动和横滚扰动低频分量的有效隔离。仿真结果表明,该方法能够大幅衰减陀螺测量噪声和横滚扰动高频分量引起的方位电机力矩扰动幅值,增强系统稳定性。最后通过某二维陀螺平台进行了实验,过顶位置时瞄准线方位经受振动条件下的稳定精度由82.4 μrad 减小为44.6 μrad,经受摇摆条件下的隔离度由?14.54 dB提升至?27.85 dB。实验结果验证了该方法能够有效提升过顶位置方位瞄准线的扰动隔离性能。 相似文献
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In this paper, we have studied the hybrid projective synchronisation for incommensurate, integer and commensurate fractional-order financial systems with unknown disturbance. To tackle the problem of unknown bounded disturbance, fractional-order disturbance observer is designed to approximate the unknown disturbance. Further, we have introduced simple sliding mode surface and designed adaptive sliding mode controllers incorporating with the designed fractional-order disturbance observer to achieve a bounded hybrid projective synchronisation between two identical fractional-order financial model with different initial conditions. It is shown that the slave system with disturbance can be synchronised with the projection of the master system generated through state transformation. Simulation results are presented to ensure the validity and effectiveness of the proposed sliding mode control scheme in the presence of external bounded unknown disturbance. Also, synchronisation error for commensurate, integer and incommensurate fractional-order financial systems is studied in numerical simulation. 相似文献
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针对现代飞机高集成度机电管理系统的测试与仿真需求,提出一种基于PXI技术的新型机电管理系统综合检测系统设计与实现方案。在该方案中,机电管理系统的所有信号经过信号接口盒后进入到综合检测系统中,通过断点模块连接机电管理系统产品,在断点模块可以对综合检测系统的所有信号进行监控测试、信号验证及分析处理;通过硬线、RS422总线、GJB289A总线、ARINC429总线形式将机电管理系统和机电管理系统综合检测系统相连接。该系统可有效节省硬件资源、准确实现信号级故障隔离,可实现机电管理系统硬件和软件的独立检测并且可实现多台机电管理系统的测试和检验;与传统手动检测相比,可以平均节省60%的检测时间。通过测试和试验,机电管理系统综合检测系统工作稳定、可靠。 相似文献
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In this paper, a two-input two-output secure communication scheme based on a four-wing four-dimensional chaotic system with disturbance inputs is discussed. Based on parameter modulation theory and Lyapunov stability theory, synchronization and secure communication between transmitter and receiver are achieved and two message signals are recovered via a convenient robust high-order sliding mode adaptative controller. In addition, the gains of the receiver system can be adjusted continually, the unknown parameters can be identified precisely and the disturbance inputs can be suppressed simultaneously by the proposed adaptative controller. Synchronization under the effect of noise is also considered. Computer simulations are done to verify the proposed methods and the numerical results show that the obtained theoretic results are feasible and efficient. 相似文献
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Synchronization of uncertain fractional-order chaotic systems with disturbance based on a fractional terminal sliding mode controller 下载免费PDF全文
This paper provides a novel method to synchronize uncertain fractional-order chaotic systems with external disturbance via fractional terminal sliding mode control. Based on Lyapunov stability theory, a new fractional-order switching manifold is proposed, and in order to ensure the occurrence of sliding motion in finite time, a corresponding sliding mode control law is designed. The proposed control scheme is applied to synchronize the fractional-order Lorenz chaotic system and fractional-order Chen chaotic system with uncertainty and external disturbance parameters. The simulation results show the applicability and efficiency of the proposed scheme. 相似文献
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目前在模拟电路故障诊断及测试过程中存在两个问题:测试信号的连续性及容差特性造成的测试信号数量巨大,故障知识表示复杂,测试程序(Test Program,简称TP)的编写多用基于决策知识的人工生成方法。通过对IEEE1232标准的体系结构和诊断推理机要求的分析,论文对IEEEE1232模型体系进行扩充,提出一种包含特征提取技术和多种AI诊断方法的诊断知识库生成协议,设计并实现了符合1232标准知识库的TPS自动生成测试系统。提高了诊断知识的移植性,实现了TPS的自动生成。仿真结果证明了该方案的可行性 相似文献
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A scheme to implement the controlled‐NOT (CNOT) gate for quantum systems is proposed, which is based on Lyapunov control. The scheme does not require precise control of the interaction time since the system is stable when the control fields vanish. In particular, the control fields can be easily obtained by most initial states. As an example, the CNOT gate is realized for two atoms trapped in an optical cavity by exploiting two disturbance cases. Compared to continuous disturbance, the fidelity of the CNOT gate is higher under impulsive disturbance, however, interaction times are much longer. Numerical simulations indicate that the scheme is robust against variations of control parameters and decoherence caused by atomic spontaneous emission and cavity decay. Therefore, the scheme may provide useful applications in quantum computation. 相似文献
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Sara Dadras 《Physica A》2010,389(12):2434-2442
This paper deals with designing a sliding mode controller (SMC) for a fractional-order chaotic financial system. Using the sliding mode control technique, a sliding surface is determined. The sliding mode control law is derived to make the states of the fractional-order financial system asymptotically stable. The designed control scheme is robust against the system’s uncertainty and guarantees the property of asymptotical stability in the presence of an external disturbance. An illustrative simulation result is given to demonstrate the effectiveness of the proposed sliding mode control design. 相似文献