Entomological Radar Overview: System and Signal Processing

Insect migration is a significant ecological phenomenon in nature, and difficult to directly observe because insects are small and fly hundreds of meters above the ground at night. Radar, working in all-weather and all-time conditions, remains one of the most effective tools for observing insect flight. This paper reviews the developments of radar systems and signal processing methods in radar entomology. Typical insect radar systems and parameter retrieval methods are presented, including that the scanning insect radar and Vertical Looking Radar (VLR) achieve the retrieval of the insect parameters, such as density, mass, orientation, wingbeat frequency. In addition, some cases of advanced radar techniques and signal processing are provided to give insight on current developments of insect parameter retrieval. For example, a new insect radar system now is being researched and developed in China, which consists of one high-resolution-phased array radar and three multi-frequency and fully polarized radars, by adopting modern radar techniques, such as high resolution technology, full polarization technology and distributed radar technology and so on. The new insect radar system will be crucial to monitor insect migration, both for scientific research and as an early warning system for pests.

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