{'fraction_non_alphanumeric': 0.014891179839633447, 'fraction_numerical': 0.0, 'mean_word_length': 5.287769784172662, '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}}
Dynamic composite scattering from low altitude target over sea surface

The theoretical and experimental analyses are carried out to investigate the features of the composite scattered field. The reduced-order electric-magnetic current iteration method is proposed to rapidly calculate composite scattering of a target over sea surface. The computation of the surface current radiation integral is accelerated by the fast far field approximation algorithm (FaFFA) with adaptive grouping. Experiments with pulse-Doppler dynamic measurement system are conducted to validate the proposed method. Moreover, the pulse width of the receiver channel is determined based on the multipath effect, and thus the echo signal from the target in the presence of the sea surface can be extracted. It is of great benefit to detect low altitude targets over sea background using the system.