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以X-51A为例,研究了飞艇红外探测系统对临近空间高超声速目标的探测性能。首先,根据飞行器的飞行状态和飞行高度建立了临近空间高超声速目标不同波段的红外辐射特性模型,以及随高度变化的目标背景红外辐射强度模型;其次,综合考虑飞行器与飞艇高度、地球曲率及红外辐射在大气中传播的波段选择性等因素,建立了红外辐射在临近空间大气中传播的透过率模型;在此基础上,建立了飞艇红外探测系统对高超声速目标的探测距离模型。通过仿真得到了临近空间高超声速目标在不同飞行状态下3个波段的红外辐射强度随目标飞行高度变化的曲线,以及飞艇红外探测系统对飞行器在不同飞行状态下3个红外辐射波段的探测能力。研究结果表明:飞艇红外探测系统对高超声速目标的有效探测距离可以达到百公里量级;当飞行器飞行状态一定时,随着飞行器飞行高度的增加,系统对目标的探测距离先增大后减小;与长波波段相比,中短波波段的探测距离更大,并给出了临近空间飞艇应尽量布置在海拔高度大于18 km的高空中的部署建议。 相似文献
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A method for solving the linear-quadratic problem of Markov jump linear systems is developed in this paper, relying on the assumption of weak detectability. The concept of weak detectability generalizes previous concepts relevant to this class of systems, and most importantly, it allows us to revisit the quadratic control problem. In the main result of the paper, we show that, for weakly detectable systems, the solution obtained with the new method converges to the solution of the coupled algebraic Riccati equation that arises in the control problem if and only if the system is mean-square stabilizable. The paper shows how the concepts and the method involved are applied by means of numerical examples and comparisons. 相似文献
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提高PMT光子计数系统探测灵敏度的方法 总被引:2,自引:1,他引:1
光电倍增管(PMT)光子计数是光子计数技术的一种,通过选择合适的低噪声光电倍增管,并对光电倍增管的光阴极和前几级倍增极进行致冷。以及合理地设计光电倍增管的高压偏置电路和设定后续甄别器的鉴别闽值,可以使PMT光子计数系统对弱光的探测灵敏度达到甚至优于10^-17W。文中阐述了PMT光子计数的原理及系统组成.并对提高系统探测灵敏度的技术环节进行了分析。 相似文献
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A design method for stabilizing a multidimensional system isproposed. The deign method is developed from the viewpoint ofLyapunov stability and it is based on two Riccati like matrixinequalities those ensure the stabilizability and the detectabilityof a multidimensional system in a strong sense. The arrangementscheme of the stabilizer is set up as a combination of plantand local state estimator, which imitates the well-known compensatordesign for 1-D systems incorporated with full order state observer. 相似文献