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1.
There is shown applicability of quasi-static method for analysis of differential equations of single-circuit autodyne generator. We propose the methodology of quasi-static calculation of autodyne response taking into account of members of higher approximation order. The estimation of calculation inaccuracy in case of quasi-static method application is given, conditions of stability of the system of autodyne generator-reflecting object are considered, and comparative calculation of autodyne response for a cases of application of zeroth and tenth approximations.  相似文献   

2.
It is underlined explicit usefulness and efficiency of hardware analysis of active spectrum of non-stationery processes, necessity of automated following by frequency of input signal filters (AFFF) application as analyzing filters. It is mentioned drawbacks of analysis methods of such filters and necessity of approval possibility of frequency self-tuning of any type filters (FSAF) of high order. Possibility of FSAF and, hence, AFFF is proven in terms of application of some known features of manual regulation of electrical filters. By means of computer mathematical modeling in system VisSim/com it is proven AFFF possibility. It is underlined possibilities of some useful their application.  相似文献   

3.
Forced nonlinear precession of the magnetization vector in a normally magnetized magnetic plate under the conditions of an orientation transition is considered. It is shown that, in the field lower than the form demagnetization field, the variable circularly polarized field causes precession of the equilibrium position of the magnetization vector. It is demonstrated based on a vector model in which the precession period of the equilibrium position is inversely proportional to the squared amplitude of the variable field and the sine of the angle of deviation of the equilibrium position of magnetization from the constant field. It is shown that the critical parameters necessary for excitation of precession of the equilibrium position are the amplitude and frequency of the variable field. Diagrams determining domains of existence of precession of the equilibrium position for different saturation magnetization of a magnetic plate are constructed in terms of the coordinates variable field amplitude-frequency. The role of dissipation of magnetization oscillations in the determination of the critical parameters is elucidated. The features of precession in the presence of asymmetric excitation and in the presence of anisotropy in the plane of the plate are noted.  相似文献   

4.
基于双Wollaston棱镜的偏振测量系统的精度分析   总被引:3,自引:0,他引:3       下载免费PDF全文
为了研究航天偏振辐射计的偏振测量精度,从偏振参量的反演过程出发,结合偏振辐射定标的方法,得出Wollaston棱镜安装角度误差和因加工工艺等造成的光束非正交的角度误差对偏振测量有一定的影响。结果表明,在角度误差一定的前提下,偏振度测量误差随入射光偏振态的变化而变化;当Wollaston棱镜角度误差都控制在0.1°内,偏振度测量精度满足航天偏振辐射计的指标要求。  相似文献   

5.
基于评价室内红外无线通信信道的目的,采用改进的朗伯定律描述室内表面的漫射特性,分析了信道中直射及漫射分量的大小,定义了评价红外无线信道的瞬态响应及时延的表达方法,并针对几个实用信道进行了模拟。结果表明,光接收机的FOV及位置的变化对信道特性的影响较大。通过信道特性的分析比较,对构成高健壮性的室内光无线通信信道有积极意义。  相似文献   

6.
针对TD-LTE无线网络规划中时隙规划的需要,对TD-LTE小区帧配置方法进行了研究.首先归纳总结了TD-LTE系统吞吐量计算方法,通过仿真,验证了TD-LTE帧配置对系统容量的影响.然后研究了TD-LTE单业务小区的帧配置方法,设计建立了基于帧结构的TD-LTE小区业务吞吐量仿真平台,并对单业务小区的用户平均吞吐量进行了仿真分析,给出了部分单业务小区的最佳帧配置建议.最后,仿真分析了多业务小区的用户平均吞吐量,给出了部分混合业务下小区的最佳帧配置建议.  相似文献   

7.
男性不孕症患者精子超微结构异常的电镜诊断   总被引:2,自引:0,他引:2  
对63例男性不孕症患者的精子做了电镜超微结构观察,并做了与之对应的光镜及常规检查。除11例为死精症外,52例均为精子结构异常。52例中40例为头部异常,12例尾异常。头部异常主要为无顶体、顶体发育不良和染色质发育不良,尾异常主要为2+9+9结构异常及接柱异常。结果显示精子电镜超微结构检查能很好地避免误诊,并对精子结构异常的种类做出准确的诊断。  相似文献   

8.
It is considered carrying out the topology temperature compensation of thermostatically controlled elements on a basis of application of effect of minimal statistic inaccuracy of temperature control with purpose of minimization of temperature inaccuracy of radio engineering devices. Numerical simulation of two-dimension non-stationery temperature fields of thermostable substrate of hybrid-integral circuits is carried out, taking into account heat emission of thermostatically controlled elements and existing heat exchange mechanisms of proportional temperature controller.  相似文献   

9.
童筱涵  滕璇璇 《电子测试》2021,(4):48-49,43
本文通过对多自由度下无人船的运行情况分析,提出了多自由度的无人船建模方法,主要是通过分析建立无人船的六自由度的MMG分离型模型,并依次减少一个自由度,推导出了其五自由度、四自由度与三自由度下的数学运动模型,解决了无人船在各个自由度下的建模问题。在建模时依次讨论了各个自由度下无人船舵、螺旋桨、粘性流体动力的力与力矩模型,以及其受到的风、浪、流的干扰模型,得出了比较完整统一的各个自由度船体数学运动模型。  相似文献   

10.
The results of time-resolved photoluminescence studies of heterostructures containing monolayer arrays of InAs/GaAs quantum dots are presented. A two-component time dependence of intensity of photoluminescence from the ground state of quantum dots, with characteristic times of the slow component up to hundreds of nanoseconds and those of rapid one several nanoseconds, is studied. It is shown that the slow component is determined by the transport of nonequilibrium charge carriers between the quantum dots. At low temperatures, the time of the slow component is determined by tunneling, and at high temperatures by thermal escape of nonequilibrium charge carriers. The ratio of the contributions of tunneling and thermal escape is determined by the degree of isolation of quantum dots. A theoretical model is constructed that describes the effect of the dynamics of carrier transport on the emergence and decay of the slow component of photoluminescence.  相似文献   

11.
Evolution of concentration profiles of all types of hydrogen particles, charge carriers, active doping impurity, and distribution of the electric field in the near-surface layer of hydrogenated p-GaAs during cooling the sample after finishing the stage of introduction of hydrogen is simulated. It is shown that the form of final concentration profiles of hydrogen-containing particles and distribution of the intrinsic electric field in the hydrogenated p-GaAs layer depend on the temperature-time mode of cooling the sample. The degree of the effect of the cooling rate on the final state of hydrogenated layer increases as the doping level of semiconductor is decreased. Systematic features of formation of the final state of the hydrogen-crystal system depending on the cooling rate of the sample are presented and discussed.  相似文献   

12.
The problems of simulation and characterization of VLSI standard cell libraries designed on the basis of semiconducting CMOS-technologies of the deep submicron and nanometer level are considered. The acceleration methods of the characterization process resulted in the identification of parameters of logic cell macromodels under the multiple simulation of cells on a circuit level for different versions of input actions and under the values of process-dependent parameters and modes of circuit operation. The algorithms of constructing the circuit characterization are directed at decreasing computational expenditures and ensuring the required accuracy of the macromodels. The results of the comparative analysis of different versions of the proposed algorithms are given.  相似文献   

13.
印制电路板设计的电磁兼容性分析   总被引:1,自引:0,他引:1  
阐述了电磁环境日益复杂的情况下,印制电路板电磁兼容性设计在电子产品设计中的必要性,并在分析印制电路板造成信号传输损失、电磁能量辐射形成机理的基础上对印制电路板设计中影响印制线条阻抗的因素、阻抗匹配的重要性和如何控制信号传输线的阻抗,以及印制电路板的地线结构作了分析,从避免印制电路板形成辐射和提高其抗干扰能力的角度阐述了在印制电路板上如何合理布置地线及地线网格、地线面的应用方法,最后分析了印制电路板的布线原则。  相似文献   

14.
A method for minimization of Moore finite automata based on the operation of gluing two states and on the represention of a finite automaton in the form of a transition list is considered. Conditions of the identical operation and deterministic behavior of the finite automaton obtained as a result of gluing two states are presented. Cases of formation of wait states as a result of state gluing are considered. Algorithms for minimization of the number of internal states, transition routes, and input variables of Moore finite automata are described. Features of application of the proposed approach are reported.  相似文献   

15.
Scanning tunneling spectroscopy was used to obtain topographic images of the (100) surface of ultrashallow diffusion profiles of boron in silicon. This method makes it possible to study the influence of fluctuations of the surface deformation potential, which depend on the thickness of the preliminary deposited oxide layer and on the crystallographic orientation of the fluxes of nonequilibrium vacancies and self-interstitials that stimulate the exchange mechanisms of impurity diffusion. The existence of self-assembled systems of quantum anti-dots, which are formed due to fluctuations in the surface deformation potential and which are microdefects that penetrate through the diffusion profile of the dopant, is demonstrated for the first time. It is established that a spread in the sizes of quantum anti-dots is reduced with increasing temperature of the impurity diffusion. In addition, the sizes of quantum anti-dots are found to be interrelated to their spatial distribution, which is indicative of a fractal mechanism of formation of self-assembled zero-dimensional systems under conditions of strong interaction of the flux of impurity atoms with that of primary defects. Self-assembled quantum anti-dots embedded into a system of silicon quantum wells make it possible to design microcavities with distributed negative feedback; the existence of such microcavities is confirmed by spectral dependences of the reflection and transmission coefficients in the visible and infrared regions of the spectrum, respectively.  相似文献   

16.
卢道明 《光电子快报》2018,14(3):236-240
The negativity of Wigner function (WF) is one of the important symbols of non-classical properties of light field. Therefore, it is of great significance to study the evolution of WF in dissipative process. The evolution formula of WF in laser process under the action of linear resonance force is given by virtue of thermo entangled state representation and the technique of integration within an ordered product of operator. As its application, the evolution of WF of thermal field and that of single-photon-added coherent state are discussed. The results show that the WF of thermal field maintains its original character. On the other hand, the negative region size and the depth of negativity of WF of single- photon-added coherent state decrease until it vanishes with dissipation. This shows that the non-classical property of single-photon-added coherent state is weakened, until it disappears with dissipation time increasing.  相似文献   

17.
Methods of functional-logical simulation of the radiation behavior and effect of electromagnetic radiation on integrated circuits (ICs) based on the model of the Brauer digital fuzzy automation are considered. A principal distinction of this method from conventional ones is the possibility of taking into account the dependences of radiation resistance and pulsed electric strength on operation mode, functional state, and construction- topological and circuit parameters of ICs in the explicit form in functional-logical models of ICs. The procedures of construction of membership criterion functions of basic elements for ICs of various technologies are considered. Algorithms and recommendations for methods of predicting pulsed electric strength and transient and residual radiation effects in ICs are given. As an example, theoretical and experimental results of simulation of the quality of functioning of LSIC ROM of a series 1656 with respect to residual damages are presented.  相似文献   

18.
上世纪60年代初,香农的学生Gallager在他的博士毕业论文中首次提出了LDPC码的概念和完整的译码方法,但是直到上世纪末期,随着LDPC码译码理论的进步和计算机技术的发展,LDPC码才以其优良的误码性能和良好的可实现性成为人们研究的焦点。针对QC类LDPC码进行研究的时候,注意到很多码的循环子矩阵中不只有一组1,这就产生了水平运算后判断运算结果属于哪个存储模块的问题;另外,由于校验矩阵中每个循环子矩阵的列初始位置都是不同的,而且通常LDPC码的校验矩阵的循环子矩阵的数目都是非常庞大的,因此如果通过程序固化的方法,不但容易出现不易排查的错误,而且开发效率会大大下降。为解决该问题,并将解决方案通用化,文中以校验矩阵中循环子矩阵中1的排列特点为研究对象,找到引起变化的量之间的共性特征,从而实现通用化模块的设计。  相似文献   

19.
李文强 《电子测试》2016,(19):81-82
在当今社会物联网是一个新兴的产业同时也是人们研究的重点.但是不管是对于物联网的认识还是对于物联网的研究都还处在初步的探究阶段.本文立足于物联网的概念,对我国物联网的发展现状以及发展中存在的问题进行分析.并且对物联网的关键性技术进行阐述.希望更好的促进我国物联网技术的发展.  相似文献   

20.
针对雷达等机电产品的基础共性问题,以其机械系统为核心,进行虚拟产品研发技术研究,提出了复杂机电产品虚拟装配、自动化仿真、CAE计算结果可视化发布的解决方法,突破了基于人自然操作的交互式虚拟装配、数字样机高级仿真、CAE计算结果可视化等关键技术,解决了基于人自然操作的自动装配、基于可配置模板的自动仿真以及CAE计算结果的重构等难题,实现了对雷达等机电产品研发过程中基于数字样机技术的虚拟产品自动化装配设计、自动化仿真以及CAE计算结果的发布,形成了雷达虚拟产品集成研发平台。  相似文献   

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