Monitoring of Cardiorespiratory Signal: Principles of Remote Measurements and Review of Methods

Physiological signs can be remotely observed from the physiological and physical effects caused by a cardiorespiratory activity. A wide range of research on remote cardiorespiratory monitoring systems has been done using different methods, including methods based on Doppler effect, thermal imaging, and video camera imaging. The aim of this paper was to review and compare the newest and most promising of such remote measuring methods, introducing their merits and limitations under different circumstances. In addition, this paper summarizes the performance of these methods in a table regarding the noise artifacts, subject movement, the number of regions of interest, generalization to multiple subjects, detection range (distance), biological effects, and cost. This is a thorough general overview of the remote measurement of cardiorespiratory methods.