A metasurface-loaded low-scattering struts for sidelobe reduction in front-fed reflector antenna

Abstract A metasurface-loaded low-scattering strut has been proposed to reduce the radiation side lobe levels (SLLs) of front-fed reflector antennas. The H-shaped metasurface unit cells help to reduce the radar cross section (RCS) of metallic feed-support struts and finally reduce the SLLs. Compared to the metallic strut, the designed low-scattering strut reduced the forward RCS by 8.8 dB and the total RCS by 4.2 dB at 2.78 GHz. The technique is implemented in a 2 m S-band reflector antenna, and the SLL of the reflector antenna with the low-scattering struts is reduced by 4.0 dB compared to the reflector antenna with metallic struts. The reason for the significant SLL reduction in the reflector antenna utilizing low-scattering struts is explained. The simulation shows that, at 2.78 GHz, the SLL is lower than -21.8 dB. The result proves that the low-scattering strut design can be used to reduce the SLL on the front-fed reflector antenna.