Optimization of radome wall and joint for X-band reflector antenna using Floquet modal analysis

Abstract

The performance of high frequency weather radars becomes questionable when the antenna system is enclosed by a radome because losses are more at higher frequency. To achieve high performance and accuracy, the radome wall and joints should be designed and optimized properly. Current manuscript presents the detailed study of A-sandwich radome wall and joint characteristics derived for polarimetric Doppler Weather Radar reflector antenna at X-band frequency. The diameter of the reflector antenna is 2.4 m which will be protected by a spherical A-sandwich radome of diameter 4.2 m. Radome wall is optimized by parametric variation of skin and core thickness using Floquet’s modal analysis in Ansoft HFSS Software package. Performances of radome panel with three different joint cross-sections have been compared in terms of insertion loss and phase variation and the best one is proposed for X-band antenna radome. Measurement was carried out at Compact Antenna Test Facility where the joint of two flat rectangular radome panels was hanged vertically in front of reflector antenna. Simulated results are compared with measured results to validate the proposed design.

Keywords:

• A-sandwich radome
• insertion loss
• insertion phase variation
• Floquet modes
• HFSS software

Acknowledgement

Authors are thankful to Shri R. Ranga Rao and Shri T. Satyanarayana from Radar Development Area, ISTRAC for all kind support and encouragement. They are also thankful to EDMD/SIG, ISAC to provide test facility in CATF. They also acknowledge Mechanical System Group, ISTRAC for fabrication of test panels.