Original title: Radar-Based Vital Signs Sensing in Vehicles
Translated title: Radar-Based Vital Signs Sensing in Vehicles
Authors: Svoboda, Martin ; Kaczmarczyk, Václav (referee) ; Valach, Soběslav (advisor)
Document type: Master’s theses
Year: 2026
Language: eng
Publisher: Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií
Abstract: This diploma thesis investigates the feasibility of measuring human vital signs in a vehicle interior using a 60 GHz FMCW MIMO radar. The theoretical part describes the operating principles of FMCW radars, range and phase measurement, angular processing with antenna arrays, and the limits imposed by chirp design. It also summarizes relevant literature on radar-based vital-sign sensing, with emphasis on in-vehicle use, where body motion, vehicle vibrations, clutter, multipath propagation, and the overlap between breathing and heart-rate harmonics make the task difficult. The practical part describes the construction of a radar measurement system based on the TI AWR6843ISK and DCA1000EVM boards, including radar attachment, reference sensor selection, radar data processing, target tracking, and exploratory visualization tools. Several methods for vital-sign extraction were tested, including STFT analysis, band-pass filtering with Hilbert-transform-based instantaneous frequency estimation, correlation-based approaches, and a sliding-window FFT method. Heart-rate extraction proved unreliable in the measured data, mainly because the HR signal was weak and often overlapped with breathing harmonics. The work therefore focuses on breathing-rate-related features as a more robust indicator of human presence. The final evaluation compares human target tracks with strong inanimate reference tracks in several parked and driving scenarios. The results show that breathing-related amplitude, detrended phase, and non-zero Doppler-bin power can provide useful separation between humans and inanimate objects, with average SNR values generally above 20 dB. The work does not yet provide a finished production-ready vital-sign monitor, but it establishes a working radar processing chain, identifies the main practical limitations, and gives a basis for future development of in-vehicle radar-based occupancy and passenger-state monitoring.
Keywords: FMCW radar; MIMO System; vital signs monitoring; FMCW radar; MIMO System; vital signs monitoring

Institution: Brno University of Technology (web)
Document availability information: Fulltext is available in the Brno University of Technology Digital Library.
Original record: http://hdl.handle.net/11012/257332

Permalink: http://www.nusl.cz/ntk/nusl-774175


The record appears in these collections:
Universities and colleges > Public universities > Brno University of Technology
Academic theses (ETDs) > Master’s theses