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 The effective noise figure of a nondegenerative parametric amplifier, loaded with a noisy second stage, is derived and expressed in terms of the coupling factor and the normalized negative conductance. The optimization of the effective noise figure of the system is then discussed in detail. The gain of the amplifier is also given in terms of the coupling factor and the normalized negative conductance, the relationship between the gain and the effective noise figure is thus found. An upper limit of the... The effective noise figure of a nondegenerative parametric amplifier, loaded with a noisy second stage, is derived and expressed in terms of the coupling factor and the normalized negative conductance. The optimization of the effective noise figure of the system is then discussed in detail. The gain of the amplifier is also given in terms of the coupling factor and the normalized negative conductance, the relationship between the gain and the effective noise figure is thus found. An upper limit of the bandwidth of the amplifier is established in view of the optimum noise performance. Finally, a method of synthesis is suggested with numerical illustrations.  本文首先推导了级联着一个噪声很高的次级的参量放大器系统的有效噪声系数,并且用耦合系数和规一化负电导来表示;然后详细地讨论了这个有效噪声系数的最佳化问题。因为放大器的增益也可用耦合系数和规一化负电导来表示,因此在增益和有效噪声间获得一个单值关系式。从最佳噪声运用角度出发建立了放大器通带的上限值。最后,提出一个新的综合方法,并用数字例子作说明。  The problems concerning the voltage adjustment of the power supply system of pulsed laser and its accuracy are discussed. Emphasis is laid on the analysis of the accuracy of voltage adjustment and the factors influencing the voltage accuracy involved in the clipping charging method and measures for improvement are proposed. As for the method of continuous charging, discussions are mainly directed to the methods of voltage adjustment, the optimization design of the parameters and the accuracy of the various... The problems concerning the voltage adjustment of the power supply system of pulsed laser and its accuracy are discussed. Emphasis is laid on the analysis of the accuracy of voltage adjustment and the factors influencing the voltage accuracy involved in the clipping charging method and measures for improvement are proposed. As for the method of continuous charging, discussions are mainly directed to the methods of voltage adjustment, the optimization design of the parameters and the accuracy of the various voltage adjustment methods.  本文讨论了脉冲激光电源系统的电压调节和调压精度问题.对于阶梯充电方式,着重分析其调压精度以及电压精度的影响因素与改善措施.对于连续充电方式,主要讨论其电压调节方式、参数的最佳化设计方法以及各种调压方式的精度问题.  A fast iteration algorithm for one dimensional unconstraint optimization problems of convex functions is suggested. The advantages of this method as compared with such wellknown methods as the Golden Section Method, the Parabolic Method, the DSC Method and the Powell Method are twofold:First, this method ensures that the difference between the final calculated optimum (stoppingoptimum) Ci* and the actual optimum C does not exceed theprescribed value δ;Second, this method provides a contraction ratio... A fast iteration algorithm for one dimensional unconstraint optimization problems of convex functions is suggested. The advantages of this method as compared with such wellknown methods as the Golden Section Method, the Parabolic Method, the DSC Method and the Powell Method are twofold:First, this method ensures that the difference between the final calculated optimum (stoppingoptimum) Ci* and the actual optimum C does not exceed theprescribed value δ;Second, this method provides a contraction ratio (△i△i+1)/△i greater than 0.5. The acceleration of the contraction of the search range is achieved by utilizing more function values.  本文给出一个解凸函数一维无约束最优化问题的快速迭代算法.它较熟知的0.618法、抛物线法、DSC法或Powell法具有如下优点:1.能保证停算时的最优函数值与问题的最优解的函数值之差不大于给定的δ值.2.利用较多的已求得的函数值,使探索区收缩更快.收缩比率(△_i△_(i+1))/△_i超过0.5.   << 更多相关文摘 
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