In this article, airborne broadband (maximum 400 MHz bandwidth) C-band circularly polarized synthetic aperture radar (SAR) is proposed and developed for further study on compact (CP SAR) system using circular polarization. This article explains the scattering characteristic of polarization as concept SAR, configuration, RF antenna, ground test, flight test SAR in Hinotori-C2 (Firebird-C2) missi...