Coupled structural-electromagnetic modeling and analysis of offset reflector antennas

With the development of offset reflector antennas with high performance, the growing demands for high frequency, low sidelobe level and reduced mass have brought structural design and manufacturing process stringent requirements. The coupled structural-electromagnetic problem of offset reflector antennas is studied to find out the prime structural factors which have a great effect on electromagnetic performances, thereby reducing the requirements of minor structural factors effectively. Considering the structural factors such as the reflector surface errors and the feed errors, the coupled structural-electromagnetic model of the offset reflector antenna is discussed and developed by using the aperture field method. The coupled analysis results of the electromagnetic performance of a 2.6-m spaceborne offset antenna with surface thermal distortions caused by solar radiation shows the proposed coupled model is effective and of potential engineering value.