Deformation And Stress Analysis For Paraboloid Antenna Reflector

Antenna structure is composed of reflector and antenna frame which is used to support the reflector. Reflector is the primary component of antenna structure to send and receive electromagnetism signal. So the surface precision of reflector direct influences the electromagnetic performance of antenna. In this paper, the deformation property of reflector under loading effect is researched by elasticity theory of thin shell. The displacement and stress fields of reflectors constrained by several different types of edge in engineering are analyzed and compared, and the law of edge constraint effect on reflector's deformation property is summarized. Different from previous mechanical analysis of antenna structure, the displacement and stress fields of reflectors are obtained by analytic method in this paper.At analyzing antenna structure's mechanical property, the reflector is seen as a thin shell model, and its constraints are simplified as a top point support and an edge constraint. After the simplification including the steps of changing partial differential equations into constant differential equations, element elimination and integral, the shell deformation equation is turned into the displacement method basic equation. And the boundary condition of top point support and edge constraint is proposed. Thus the definite problem of reflector deformation equation is established.In calculation process, a power series method and a method based on expansion reflector deformation equation according a small parameter in the equation are used to resolve small-diameter and large-diameter paraboloid antenna reflectors deformation problem respectively. On the based of the result of displacement and stress fields, the deformation characteristic of reflector is analyzed detailedly.For embodying the influence of edge constraint to reflector's deformation property, the deformation characteristics of reflectors constrained by free edge, rigid edge and elastic edge are all analyzed and compared in this paper, which rigid edge and elastic edge effect on reflector's displacement fields, and the relation between the effect and the geometric parameters of reflector are summarized emphatically.