VHF雷达空域干涉法探测曲靖电离层E区场向不规则体精细结构

Fine structure of ionospheric E-region field-aligned irregularities revealed using the Qujing VHF radar spatial interferometry

针对VHF相干散射雷达传统观测方式的探测能力局限,构建了空域干涉法探测实验系统,其具备对电离层场向不规则体(field-aligned irregularity,FAI)三维精细结构探测能力.结合曲靖E区FAI干涉探测实验数据,实现了对系统相位偏差校正及回波三维空间位置精确获取,得到了不规则体云团的三维精细结构以及漂移运动过程,包括FAI回波散射点的三维空间位置以及FAI云团的三维空间外尺度、漂移运动轨迹和漂移速度等.探测实例结果表明:其东西、南北和高度向分布范围分别为-35~20 km、85~120 km和95~130 km,对应的三维外尺度分别为23.8 km、7.6 km和7.6 km;东西向漂移速度要大于其他两个方向,并呈现出5~6 min的准周期回波特征.

Aiming at the limitation of detection ability of VHF coherent scattering radar in routine mode,a detection system based on interference method is constructed to form the detection ability of three-dimensional fine structure of ionospheric E region field-aligned irregularity(FAI)in this work.Based on E region FAI echo data obtained by VHF radar interference detection experiment carried out at Qujing,the phase deviation of detection system is calibrated and the three-dimensional fine structure and drift motion process of E region FAI are obtained.It includes the three-dimensional position of the FAI echo scattering point and the three-dimensional outer scale of the FAI cloud cluster,drifting trajectory and drifting velocity,etc.Observed results show that the east-west,north-south and altitude ranges of E region FAI structure are within-35-20 km,85-120 km and 95-130 km,respectively,and the corresponding three-dimensional outer scales are 23.8 km,7.6 km,and 7.6 km,respectively.The drift velocity in the east-west direction is greater than that in other directions.Quasi-periodic echoes with the period of 5-6 min are also presented in this study.It completely and accurately reveals the spatiotemporal evolution process of FAI in the E region from generation to disappearance.