{'fraction_non_alphanumeric': 0.017569546120058566, 'fraction_numerical': 0.01903367496339678, 'mean_word_length': 4.896551724137931, '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}}
UWB elliptically-tapered antipodal Vivaldi antenna for microwave imaging applications

An elliptically-tapered antipodal Vivaldi antenna with operating frequency range from 1.65 GHz - 18 GHz designed for microwave imaging applications is presented. It includes comb-shaped slits and opening elliptical rate of top and bottom radiators to lower frequency band limitation of conventional antipodal Vivaldi antenna. It is shown that the antenna gain has been increased by comb-shaped slits at lower frequencies up to 9.5 dBi at 2 GHz and at higher frequencies up to 14.2 dBi at 18 GHz. Feasibility of the proposed antenna for the use in microwave imaging technique is also demonstrated.