Presence Detectors and Remote Heartbeat Sensing Using Radar Technology

Sammanfattning: Presence detectors based on different technologies have been around for many years now, with a constant expansion of situation implementations. In this thesis, an overview of the capabilities of different types of presence detectors has been done and the radar technology have been further investigated. A 60 GHz pulsed coherent radar has been used to measure the limits of the radar sensor’s distance and movement capabilities to extract motions originating from the heartbeat. With the radar set to a constant distance measurements of different aspects of the heart-beat characteristics as well as breathing pattern and its influence on the heart rate were performed.Measurements of the authors’ chest movement from breathing and heart beats have been performed to yield information about the morphology of the chest move-ment based on the characteristics of the heartbeats. A neural network was set upand trained by data sets from heartbeat movements while holding the breath to identify the small changes of heart beats from different persons and to classify and predict who the heartbeat belongs to. An average success rate of 90 % was achieved when predicting which person the heartbeat sequence belong to.The heart rate variability (HRV) has also been a subject to investigation where the breathing pattern is taken into account for changes in the heart rate through-out the breathing cycle. The results indicate a promising method of measuring breathing pattern, heart rate and corresponding heart rate variability needing no physical contact.