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Phased Antenna Array of Radar for Small Sized Civil Helicopters

In recent years, small sized and unmanned helicopter equipment has become very widespread in the civilian area. Often when piloting small sized helicopters, there is a danger of collision with the crown of trees, unlit roofs of buildings, as well as with power lines. This problem is especially acute at night or in conditions of limited visibility. To prevent helicopter collisions with various obstacles, it is advisable to use a radar. In this regard, this article provides an overview of the concept of building a radar for small sized civil helicopters. In particular, the structures of the phased antenna arrays of the radar are considered and their directivity patterns are presented.