Estimation of sleep stages based on heart rate fluctuation and body movement

The accurate estimation of sleep stages can be used to diagnose the health condition. The conventional sleep stage estimation method, i.e., the R & K method requires expensive equipment such as polygraph machine, as well as being invasive. This paper describes a novel method to estimate the sleep stages by a using non-invasive air mattress applicable to home use. The proposed sleep stage estimation method employs two indices: H/sub rf/ (heart rate fluctuation) and B/sub m/(body movement). Based on these indices and the knowledge of sleep stages, a robust sleep stages estimation method is presented.