偶发E层（Es）作为电离层中的一种典型的高电子密度不规则体，通过对其时空分布的结构和尺度、电子密度分布、漂移运动、类型等特征参数规律性的研究可以获取Es形成与大气潮汐、风场、电场、重力波、中性大气等离子体、地磁活动等因素之间的联系。我国位于Es频繁的中纬区，Es的研究一直是我国电离层物理研究和工程应用领域所关心的重要问题。针对目前Es探测现状，本项目引入相控阵天线回波到达角测量技术，研究一种基于现有单站电离层探测设备探测Es的新技术，有利于克服常规电离层观测设备多站布设带来的成本过高和单站相干或非相干散射雷达设备组成复杂、造价昂贵、维修难度大、运行成本高的劣势，不仅可获取Es探测的常规参数（临频、虚高、类型等），且可获取Es尺度、运动特征及内部不均匀体结构等参数，从而为深入理解、研究Es时空分布特性和规律，对丰富发展Es探测技术和应用研究，具有十分重要的科学意义。

The Sporadic E layer (Es) is a typical irregularity of high electron density in the ionosphere, by the means of research of its spatial and temporal distribution of the structure and scale, the distribution of electron density, the drift characteristic parameters, type, etc. we can obtain the link between the Es generation and the factors, such as atmospheric tides, wind field, electric field, gravity waves, the neutral atmospheric plasma, geomagnetic activity and others. As the country located in the mid-latitude area where Es frequently occured， Es research has been a major concern of ionospheric physics research and engineering applications in China. Refering to the current research of Es detection, this project introduces an echo direction of arrival measurement techniques based on phased array antennas, aims to develop a new Es observing method which will be implemented in the existing monostatic ionospheric sounding system. This will help us to overcome the disadvantages of complex equipment components, expensive prices, large maintenance difficulties, huge operating spends included in the coherent or incoherent scattering radar and the high cost caused by muti-station conventional ionospheric obsernation equipment layout. Not only be able to get the general parameters of the Es(critical frequency, virtual height, type, etc.), but also get Es scale, movement characteristics and internal irregularities' structure parameters. Depending on this, so as to deeply understand the Es temporal and spatial distribution characteristics and laws, this study has a very important scientific significance to enrich the development of Es detection technology and application research.