Design of the composite casing of microstrip antenna for the aerospace satellite

Purpose: The paper aims to present a design and numerical verification procedure of a composite casing of a microstrip antenna for an aerospace satellite. Design/methodology/approach: The casing for the microstrip antenna was designed in a form of a laminate shell with variable number of layers of reinforcing fabric. The material properties, both static and dynamic, were determined experimentally and then exported to an environment of numerical analyses. The numerical modal analysis allows optimizing the geometry and lay-up of the casing in such a way that a number of modal shapes occurring in the operational frequency band was significantly reduced, several modal shapes with high displacement in flanges of the casing were eliminated and the values of natural frequencies were increased. A final model of the composite casing was subjected to two types of analyses which simulate typical operation conditions during spacecraft mission. These analyses contained thermomechanical quasi-static analyses with 12 loadcases and thermomechanical shock analyses with 9 loadcases, which simulate various mechanical and temperature conditions. Findings: Results of the performed analyses were compared with safety margins determined by following requirements to spacecraft vehicles. The obtained results confirm the design feasibility, which allow considering the proposed design during manufacturing of a prototype in further studies. Practical implications: Moreover, the presented results can be considered as a design methodology guideline, which can be helpful for engineers working in the aerospace industry. Originality/value: The originality of the paper lies in the proposed design and verification procedure of composite elements subjected to operational loading during a spacecraft mission.