Development of Non-Uniform Circularly Polarized Array Antenna for Synthetic Aperture Radar Sensor

摘要

An L-Band (1.27 GHz) Circularly Polarized Synthetic Aperture Radar (CP-SAR) sensor has been developed in Josaphat Microwave Remote Sensing Laboratory (JMRSL), Center for Environmental Remote Sensing, Chiba University. The CP-SAR sensor will be installed on unmanned aerial vehicle (UAV) and on-board small satellite (μSAT CP-SAR) as well as. Some applications are offered for this sensor such as land cover mapping, disaster monitoring, snow cover, oceanography mapping, etc. To maintain the quality of SAR data recording, a low sidelobe level array antenna is required to be implemented in the SAR system. In this papa, the Dolph-Chebyshev weighting algorithm for 20 dB sidelobe level is applied to manage the non-uniform power distribution in array antenna. A method of moment (MoM) is employed for optimizing the design and achieving a good circular polarization at the targeted frequency. The both measured and simulated results have good agreement with the theoretical design. The low side lobe level and reasonable gain indicate the antenna is satisfying the specifications of CP-SAR sensor.