Modal Analysis of the Holistic Structure of a Planar Phased Array Radar

In order to research the dynamic characteristics of the holistic structure a planar phased array radar,the method of discrete distribution then merging is applied to establish the finite element model of the structure, and the modal parameters are obtained by the Lanczoc method. The results show that the natural frequency of the structure avoids its own rotating excitation frequency and the possibility of resonance accident under the condition of 30 r/min is small;that the centroid of antenna module has deviation from the rotary center is the important factor that causes the first order frequency low; the modal parameters of first to sixth order reflect that the vehicle platform, lifting devices possess good stiffness; the maximum deviation displacement appears at the horizontal and vertical antenna frame girder joint, and it is decreased effectively after the optimization by triangle floor structure.