{'fraction_non_alphanumeric': 0.01107011070110701, 'fraction_numerical': 0.023370233702337023, 'mean_word_length': 5.2615384615384615, '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}}
Volume inspection of composite structures in aircraft radomes with FMCW terahertz radar at 100 and 150 GHz

We present a terahertz imaging system for aircraft radome inspection based on a dual-frequency FMCW radar working at center frequencies of 100 and 150 GHz and with 40 and 60 GHz bandwidth, respectively. The imaging sensor combines two all-electronic multiplier chains at the respective frequencies and is integrated in the production environment of radomes built of glass fiber-reinforced composite structures. While images acquired at the two distinct working frequencies can yield different information of possible structural defects, at the same time, a data fusion algorithm is applied combining the signals of both terahertz sensors for enhanced depth resolution by a total FMCW bandwidth of 100 GHz.