{'fraction_non_alphanumeric': 0.028999064546304958, 'fraction_numerical': 0.0205799812909261, 'mean_word_length': 4.911602209944752, '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}}
Noncontact Vital Sign Detection using 24GHz Two-Dimensional Frequency Scanning Metamaterial Leaky Wave Antenna Array

This paper presents a noncontact vital sign detection scheme using a two-dimensional (2-D) frequency scanning metamaterial leaky wave antenna (L W A) array at 24 GHz band. To avoid the self-resonance issue of interdigital capacitors and the parasitic inductance of shorted stubs, gap capacitors and vialess open stub-loaded resonators are applied to design a one-dimensional (1-D) frequency scanning metamaterial L W A which has a wide scanning angle from −62° to +71° as the frequency increased from 23.4 to 25.4 GHz, in which the broadside is at 24.1 GHz. Four 1-D frequency scanning meta material LWAs and a series feeding network are combined to realize 2-D beam scanning. Noncontact vital sign detections using the proposed 2-D frequency scanning metamaterial L W A array can detect multiple persons with different heights. For demonstration, the respiration rate and heartbeat rate of two persons with standing and sitting postures are measured.