昆虫雷达数据实时采集、分析系统

A scanning entomological radar was recently commissioned by the Institute of Plant Protection of the Chinese Academy of Agricultural Sciences for use in studies of the migratory flights of Heliothis armigera moths, and other insect pests of agriculture, in northern China. The radar differs from previous scanning entomological radars in its use of digitized rather than analogue signals in the production of a plan-position indicator (PPI) display. To enable efficient extraction of migration data from the radar observations, a secondary signal-processing system has been developed to acquire and analyze the display images. In this system, the VGA signal from the radar's digital PPI display is captured as either a single-frame or a multiple-frame bitmap. The secondary analysis then eliminates distortions and range rings, identifies insect dot-echoes, and generates a dataset of echo positions (3 dimensions) and intensities. Analysis of multiple-frame bitmaps additionally allows echo speeds and directions to be determined and ground clutter echoes to be eliminated. Migration parameters for the overflying population - density, speed, direction, flux, collective orientation - and their variances are estimated from these datasets, and profiles of these quantities can be obtained by the usual scanning entomological radar technique of observing at a sequence of antenna elevations. This computer-based image-analysis technique has both efficiency and objectivity advantages over the film-based manual analyses previously used with this entomological radar configuration, and has proved effective in recent observations of H. armigera migration. This software with the radar system was used by the IPP, CAAS at Langfang experiment station in Hebei province for monitoring the migration of cotton bollworm and other moths since 2000. The application results showed that this software could successfully deal with the radar image data collection and analyses and will become a very useful and important tool for the insect flight behavior research in the future.

该项研究利用计算机对昆虫雷达回波信号进行实时采集，并且根据昆虫迁飞特点对昆虫的迁飞方向、飞行高度、飞行速度及迁飞种群的密度和数量进行自动分析和估计，并研制监测结果的网络化远距离传播和控制技术，使昆虫迁飞的遥感监测实现自动化和智能化，同时提高昆虫雷达数据分析的精确度和时效性，为迁飞性害虫发生危害的及时预测和治理提供依据。