【作者】 张晓明；

【导师】 孟萃；

【作者基本信息】 清华大学 ， 核科学与技术， 2011， 硕士

【摘要】 核爆炸产生的γ射线等与空气分子相互作用会产生核电磁脉冲（NEMP），它是核爆主要的危害方式之一。通常核电磁脉冲具有场强高、上升时间快等特点，对其的研究自核试验开展之初便一直受到重视。近几十年来，随着信息产业的发展，除了核电磁脉冲之外，能够对信息设备造成危害的高功率电磁(HPEM)环境也逐步引起了人们的重视。而它的范围则更加广阔，包括雷电电磁脉冲（LEMP）、高功功率微波（HPM）、超宽带（UWB）、静电放电（ESD）和大功率开关动作等，其涉及的领域包括通信、交通、能源等方方面面。高功率电磁环境最主要的危害方式是瞬态电磁场的耦合效应，其能够对相关军事和民用设备产生不同程度的干扰和破坏，对其的防护已经成为当今发达国家研究的重要基础性课题之一[1]。而这些研究的基础之一就是对其时域波形进行准确的测量。对于瞬态电场的测量一直以来是高功率电磁场领域研究的热点，现在也存在着很多类型的电场传感器。总的来讲，国内的研究水平较国外发达国家相比还存在着较大的差距，这也严重限制了相关研究的开展。本文所介绍的瞬态电场传感器是利用单极子天线感应外界电场，利用高输入电阻的天线接收电路进行信号处理，以满足响应的时域要求。然后通过激光器及周围电路的设计将感应的电信号转换为相应的光信号，利用光线进行光信号的长距离传输，以避免周围电磁环境对信号产生干扰。最后在接收端利用光接收机进行光电转换，通过数字示波器观察时域波形。整个系统的电路设计要满足相应的频域和时域要求，光信号与电信号之间的相互转换应避免信号信息的大量丢失。本文利用上面的原理设计并制作了一套瞬态电场传感器探头系统，并利用相关的电磁脉冲模拟器装置进行了相关的时域和频域测试。通过对测试结果的分析和研究，系统的带宽、响应时间等指标基本上满足现在相关研究开展的要求。另外在测试过程之中也发现了一些不足，这些有待后续的研究和改善。同时还对不同类型的电场传感其进行了比较研究，分析了各自的优缺点和合适的应用场合。更多还原

【Abstract】 A nuclear explosion can radiate an electromagnetic pulse (NEMP) through theinteraction of γ-rays and air molecules, and it is one of the main hazard approaches bynuclear weapons. Usually NEMP has high field strength and fast rise time. Theseyears, with the development of information technology, more and more high powerelectromagnetic (HPEM) environment has been paid attention to. HPEM includeslight EMP (LEMP), high power microwave (HPM), ultra wideband (UWB),electrostatic discharge (ESD), high power switching EMP and so on. Protection fromHPEM has become an important basic issue in developed countries. Accuratetime-domain measurement for transient field is one of the key technologies.Nowadays, there are many kinds of electric field sensors. However, foreigntechnology goes far ahead of that in China, and that severely limits the developmentof some related research.The sensor in this paper has a monopole antenna. A high input resistance circuitis connected to the antenna to satisfy time-domain and frequency-domainrequirements. Then the electric signal is modulated to an optic signal that can betransmitted by optic fiber without interference of electromagnetic field around. In theend a photoelectric conversion is conducted and the field signal can be observed onthe oscilloscope. The whole system should satisfy time-domain andfrequency-domain requirements. The conversion between electric and optic signalsshould avoid substantial loss of signal data. A sensor was designed and tested with anEMP simulator. Through the research and study of test result, we realized that thebandwidth, response time and some other parameter meet the requirements forrelevant research. Besides, some deficiencies were realized and should be improvedin the following researches. At the same time, different sensors were comparedthrough some test result, and their characters and suitable applications were studied.更多还原