Hinotori-X1 Mission: X Band Walr-Sar Onboard Boeing 737–200 Aircraft

We developed a novel concept for X-band (center frequency 9.4 GHz, HH polarization) airborne SAR, the Wide Area Long Range Synthetic Aperture Radar (WALR-SAR) onboard a Boeing 737–200 aircraft for simultaneous air and terrestrial disaster monitoring. This paper explains the configuration of our WALR-SAR system and slotted array antenna installed on the Boeing 737–200. Ground measurements of the slotted array antenna were realized to measure the characteristics of antenna and its results are discussed in this paper. Flight test of WALR-SAR onboard Boeing 737–200 in Hinotori-X1 (Firebird-X1) mission was performed during the period of 2 to 10 August 2017 at Pare-Pare and Makassar, Indonesia. Results show good performance of the WALR-SAR system and its image acquisition that covers the depression angle 0.5 to 42.0 degrees.