基于新型扫描昆虫雷达的迁飞昆虫目标检测及密度反演

我国是全球最重要的动物迁飞场，水稻、小麦、玉米等作物重大害虫在我国远距离迁飞，严重威胁我国粮食生产安全。由于昆虫迁飞多发生在夜间，雷达的全天候、全天时探测特点使其成为昆虫迁飞监测最有效的手段。扫描昆虫雷达是昆虫迁飞监测的典型体制，可获取扫描空域内迁飞昆虫数量分布、密度等。但传统扫描昆虫雷达采用两维机械扫描，扫描空域非连续，且数据率低、分辨率低，难以实现迁飞虫量与分布的准确探测。本文提出一种新型迁飞昆虫扫描雷达，采用俯仰电扫、方位机扫的高分辨相控阵体制，可对大范围空域（方位0°~360°、俯仰5°~85°）进行快速扫描，获取迁飞昆虫精细的数量分布与密度。其中，数量分布主要面临低仰角强杂波下的弱小昆虫目标检测问题；密度主要面临相控阵俯仰波位捷变下等效雷达扫描体积计算问题。为此，本文进一步提出了基于静态杂波图的自适应变参VI-CFAR检测算法与基于雷达扫描体积微元化的密度反演算法，并通过仿真与实测数据验证了方法的有效性。目前，该系统已布设于山东省东营市现代化农业示范基地开展业务运行，可获取夜间迁飞昆虫的空间精细分布与密度，成功观测到迁飞昆虫的高度成层等科学现象，可为昆虫迁飞空间结构机理分析提供关键支撑。 

Target Detection and Density Inversion of Migrating Insects Based on a Novel Scanning Insect Radar

? ?China is the most important animal migration site in the world. Pests of rice， wheat， corn and other crops migrate a long distance for procreation and breeding in China， which seriously threatens the safety of grain production. Because insects mostly migrate at night， radar is the most effective tool to monitor migratory insects by the all-weather and all-time detection capability. Scanning insect radar is a typical system for monitoring migratory insects， which can calculate the quantitative distribution and density profile of migratory insects in scan space. However， traditional scanning insect radar uses the two-dimensional mechanical scanning configuration， which has discontinuous scanning space， low data rate and low resolution. So， it is difficult to accurately measure the amount and distribution of migrating insects. A new type of scanning insect radar is presented in this paper， which adopts the high-resolution phased array radar system of pitch electronic scanning and azimuth mechanical scanning. The proposed scanning radar could quickly scan a wide range of space （azimuth 0°~360° and pitch 5°~85°）， and obtain the exact quantitative distribution and density profile of migratory insects. Nevertheless， the quantitative distribution was mainly subject to the problem of weak and small insect target detection under strong clutter at low elevation-angle； and the density profile was mainly influenced by the calculation of equivalent radar scanning volume under the jump of beam position in pitch of phased array radar. Therefore， this paper further proposed a varying parameter VI-CFAR detection method based on static clutter map and a density estimation method based on radar scanning microelement volume units， and the effectiveness of these methods are verified by simulation and measured data. At present， the system has been deployed in the modern agricultural demonstration base in Dongying， Shandong to carry out business operation， which can obtain the fine spatial distribution and density profile of nocturnal migratory insects and has observed the height stratification and other scientific phenomena of migratory insects. Key support is provided by the phased array radar for the mechanical analysis of insect migration spatial structure.