Unobtrusive Respiratory Monitoring of Sleeping Subjects by Multiple Bioradars

The development of effective personal non-contact methods for detecting sleep disorders, which may precede different health problems, is an up-to-date task of modern medicine. As was shown in recent studies, it is possible to detect sleep disorders by means of bioradar. However, the problem of view dependency of the radar-based sleep monitor performance needs to be overcome. In the present paper we presented a two-transceiver system and a signal processing algorithm for obtaining information about sleeping person respiratory rates at different positions of a human body during sleep. The proposed system was tested in a sleep laboratory of Almazov National Medical Research Centre with the participation of 5 volunteers. The performance of the proposed algorithm was estimated by comparison with a full-night polysomnography data. The achieved results showed that the designed two-channel bioradar system proved to be more accurate and robust than a single bioradar. The results might contribute to extension of bioradar sleep monitoring technology.