High-Isolation Antenna System for X-band Synthetic Aperture Radar

An antenna system for high resolution airborne synthetic aperture radar (SAR) is developed at X-band. Basic specifications of the antenna are obtained from the swath and azimuth footprint requirements of the SAR system. Series-fed printed antenna is developed to achieve these specifications. To meet stringent requirement of isolation between the transmitting and receiving antenna, an optimized ground plane with horn flares is designed. Complete antenna system is simulated and measured for return loss, mutual coupling and radiation patterns. Measured results are in agreement with the simulated results as well as the requirements of the system. Achieved isolation between the transmitting and receiving antennas is better than 64 dB at the operating frequency.