{'fraction_non_alphanumeric': 0.021292217327459617, 'fraction_numerical': 0.0, 'mean_word_length': 5.714285714285714, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Remote Programmable Temperature Stabilized Polarimetric Active Radar Calibrator with Rcs Agility for Airborne and Spaceborne Sar Calibration

This paper presents an L-band Single Antenna Polarimetric Active Radar Calibrator (SAPARC) designed and constructed at the University of Michigan in collaboration with the suborbital radar group of Jet Propulsion Laboratory. The SAPARC is intended for radiometric and polarimetric calibration of both airborne and spaceborne L-band radars, including the NASA/JPL Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) and NASA-ISRO Synthetic Aperture Radar (NISAR). The presented Polarimetric Active Radar Calibrator (PARC) is designed to have a specific scattering matrix response (equal entries) and a very large and stable radar cross section (RCS) value which is significantly higher than its passive counterparts for providing a much higher signal-to-clutter ratio. The specific scattering matrix response enables the PARC to evaluate all the radar channels' radiometric calibration constants as well as cross-talk and channel imbalances, which cannot be estimated by the passive calibration targets. The much higher signal-to-clutter ratio provided by the PARC further reduces the residual errors of calibration and allows them to be easily deployed at different target scenes during radar data acquisitions.