A Broadband MFCW Agile Radar Concept for Vital-Sign Detection under Various Thoracic Movements
Journal
IEEE Transactions on Microwave Theory and Techniques
Journal Volume
70
Journal Issue
8
Pages
4056
Date Issued
2022-08-01
Author(s)
Abstract
A multiple-frequency continuous-wave (MFCW) agile radar system has the ability to cope with various physiological conditions of a human subject. Following the mathematic model, a favorable carrier frequency for detection is pursued by analyzing the amplitude and composition of the baseband signal. In Experiment-1, a CMOS dual-band transceiver prototype emulate searching a subject from a distance. The frequencies of the dual-band system are 4.26-4.95 GHz and 17.06-19.79 GHz. During the experiment, the respiratory signal could be detected up to 12 m, and the heartbeat signal up to 6 m. Even with a wooden or a brick barrier in the path, the vital-sign detection remained satisfactory. Later, a concurrent MFCW detection is performed in Experiment-2 for more precise analyses. From the concurrent results, the breathing status can be inferred, and by cross-correlating the results after the ensemble empirical mode decomposition (EEMD) and principal component analysis (PCA), the nonlinear effects of respiratory harmonics or intermodulation tones are reduced, resulting in an accurate heart rate extraction. The receiver front-end and the signal source are manufactured using a 180-nm CMOS process, both packaged on an RO4003C printed-circuit board (PCB).
Subjects
Cross correlation | Doppler radar | dual-band transceiver | ensemble empirical mode decomposition (EEMD) | frequency agility | multiple-frequency continuous-wave (MFCW) radar | principal component analysis (PCA) | resolution | vital-sign detection
SDGs
Publisher
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Type
journal article