Microwave Noncontact Vital Sign Measurements for Medical Applications

Monitoring patients' vital sign afar decreases the medical costs and help caregivers to examine more patients in hospitals. Patients' environment also affects the vital signs, therefore, it is necessary for caregivers to observe the environmental parameters. In this paper, a network system which can gather information from distributed nodes is established to simultaneously monitor multiple patients. Sensor node which can provide patients' vital signs, as well as ambient variables such as temperature, pressure, and humidity is designed. Vital signs are obtained using 24 GHz microwave Doppler radar sensor and then compared with respiratory belt measurements. Both measurements agree with each other. The system can also be utilized to track cough and apnea real-time and provide warning signals to caregivers during emergency situations.