A transfer matrix framework approach to the synthesis of H∞ controllers

This paper presents a transfer matrix framework approach to the now well-known Riccati solution to the nonsingular H^∞ control problem. The approach taken is a frequency-domain one based on the concepts of coprime factorization and J-lossless transfer matrices that lead to the development of relatively simple method for obtaining the state-space solutions. Using two dual pairs of coupled coprime factorizations of certain chain scattering-matrices which describe the problem, we derive an identity, analogous to the Bezout identity for all stabilizing controllers, to generate all proper real-rational H^∞ controllers. We also point out the connections between algebraic Riccati solutions and J-lossless matrices.     

带光纤位相共轭器的激光振荡-放大系统

介绍了采用光纤作为位相共轭镜应用于 MOPA(Master- Oscillator- Power- Amplifier)系统的初步实验 ,利用单向环形腔振荡器输出并经一级放大 ,将放大后输出激光耦合到光纤中获得了位相共轭激光输出。当重复频率在 1～ 30 Hz变化时 ,远场发散角为 0 .6～ 0 .9mrad,相应的 M2数在 1.1～ 1.6之间变化。     

自泵浦位相共轭器中自增强现象与光致宏观电场

研究了自泵浦位相共轭器利用间歇入射光在无光照期间的新奇的自增强现象。发现采用间歇入射光可以显著缩短掺铈与掺锰钾钠铌酸锶钡单晶自泵浦江相共轭器的响应时间。通过实测晶体的光伏与热释电电场，利用电荷输运的基本模型．对实验现象给出了定性解释，且给出了进一步的实验验证。据此，分析了自泵浦位相共轭器的保真度下降的原因。     

熔石英棒和光纤构成的新型复合型相位共轭镜

提出一种使用熔石英棒和光纤构成的新型复合型相位共轭装置,并在实验中得以实现.这种组合将具有高的激光损伤阈值的大直径熔石英棒和具有较低的受激布里渊散射(SBS)阈值的光纤结合在一起,构成了振荡-放大形式的双池式受激布里渊散射结构,使得从光纤受激布里渊散射反射的斯托克斯光注入到熔石英介质中形成了强迫受激布里渊散射过程.在这种机制下,该复合型相位共轭镜较之单块熔石英棒、单根光纤或组合芯径光纤这三种形式的相位共轭镜,具有更低的受激布里渊散射阈值和更高的受激布里渊散射反射率,而且可以在较高的输入功率下运行.实验中将其用于高重复频率高功率的激光二极管(LD)抽运激光主振荡放大(MOPA)系统中,在100 Hz重复频率下获得了42.05%的反射率,并且获得了很好的光束质量,光束质量因子M2值从输入光束的3减少到1.6,反射光斑稳定.在400 Hz下光束质量因子M2值达到1.7.     

Nonlinear local J-lossless conjugation and factorization

A new definition of nonlinear local J-lossless factorization is introduced, which plays a crucial role in nonlinear H^∞ control theory. Sufficient (and in two special cases also necessary) conditions for the existence of this factorization and state-space formulae of the factor systems are given here. The main tools for the J-lossless factorization are the local right and left J-lossless conjugations, introduced in this paper. The former corresponds to the standard linear J-lossless conjugation, while the latter has no counterpart in the linear theory where it is completely dual to the former one and hence conceptually redundant. In the nonlinear case, however, this duality is much weaker and therefore the left J-lossless conjugation is essential for solving the local J-lossless factorization of unstable systems. This factorization requires a transformation of the given system to a special form and solving two independent Hamilton-Jacobi partial differential equations. Solutions of the two Hamilton-Jacobi equations have to satisfy a simple coupling condition.     

一种基于J-无损分解的性能加权函数优化设计

为了提高伺服系统性能,提出一种基于J-无损分解的性能加权函数优化设计方法.首先,依据闭环系统H_∞范数达到1的设计准则,给出了伺服系统性能加权函数优化设计算法的迭代步骤;其次,利用Bode积分关系以及H_∞最优控制结果全通特性分析了算法的收敛性;最后,基于J-无损分解推导出性能加权函数优化设计的计算公式.所提出的优化设计算法易于迭代计算,能够在较少的迭代步骤内使得闭环系统H_∞范数达到1.仿真实例验证了算法的有效性.     

(BaSr)TiO_3晶体鸟翼式互泵浦相位共轭器的研究

利用（Basr）TiO_3晶体实现了鸟翼式互泵浦相位共轭器（BWPC），实验研究了透射率随互泵浦束的入射角、入射点、泵浦比变化的规律。     

光折变相位共轭技术的研究进展

简要地介绍了光折变相位共轭技术的研究概况,着重介绍了自泵浦相位共轭镜及互泵浦相位共轭镜的研究进展,对它们的结构及机理做出了说明。     

非相干光对光折变相位共轭镜的非负效应

本文以BaTiO3:Ce自汞浦相位共轭镜为例,理论上和实验上对非相干光作用在光折变相位共轭镜的四波混频区产生的非负效应进行探讨和验证。