Modes selection for large reflector antenna structure

In order to explore some unknown territory and capture information from distant infinite space more effectively, reflector antennas tend to larger diameter and higher operating frequencies. Along with this trend, the influence of elastic deformation of antenna structure to the dynamics is much more significantly. However, the number of antenna nodes in finite element models often reach to tens of thousands, the description method for elastic deformation in node based coordinates will result in large model that hard to solve. So, the conversion of deformation description to modal coordinates will greatly reduce the computational workload and scale. Therefore, how to select key modes from a large number of modes is very important. It is crucial. Firstly, this paper describes several modal selection methods, and noted that the modal selection method for large antenna structure. Simulation results show that the method is stable and reliable. It will lay a solid foundation for the large antenna dynamics modeling and closed-loop control.