A new signal processing method for vital sensing using a Doppler sensor aiming at reliable sensingunder body movement

Vital sensing using a Doppler sensor is attractive since it does not need to put electrodes or sensors on a human body. It must be suitable for the monitoring of car drivers due to its easy use. By using this sensor, we can think about an alarm system for sudden illness of car drivers preventing them from causing accidents. However, the problem is body movements of car drivers and the vibration of the car. The Doppler sensor observes the variation of the distance between the sensor and the human body because the distance variation is yielded by the respiration and the heartbeats. Thus, the body movements of the driver are destructive for the measurement as well as the car vibration. Obviously, they cause false alarms, so the measurement must be robust against the body movement.In this paper, we propose a new signal processing method suitable for vitalsensing using a Doppler sensor. It is robust against disturbances caused by the body movement or the car vibrations. However, if these disturbances are serious, the proposed method automatically recognize the situation in order to avoid the false alarm for the car drivers’ monitoring. In addition, the proposed method is applicable to multiple persons. The performance of the proposed method is investigated through computer simulations.