A System Research On Physiologic Status Monitoring Based On Wireless Sensor Network

With the increasing degree of aging society, the number of empty nesters is also growing. If the physiological parameters of the elderly living alone are in an emergency situation but they can’t call the ambulance by themselves, it will delay the valuable time of assistance. In this thesis, establishing and improving the health monitoring system for the elderly becomes necessary. But whether it is at home or abroad, the coverage of health care and the number of allied health professionals can not meet the needs of aging population. We must find an efficient, reliable and affordable health monitoring system to achieve the real time health-status-monitoring of the elderly. Facing this kind of situation, this paper proposes a practical solution which uses the wireless sensor networks to realize the remote monitoring of human physiologic status. The main work of this paper is given as follows:Firstly, we use ATZB-24-A2 as its core processing chip; use ZigBee wireless networking technology for data transmission. We have built a stable, small and low power consumption wireless transmission network. It can ensure data transmission between nodes and the monitoring center.Secondly, with wrist as the object, device in this paper is adopted the temperature sensor named DS18B20 to make the measurement of body temperature.In accordance with the principle of temperature measurement, we have worked out the temperature measurement circuit. And we have also made research on effects of ambient temperature on the body surface temperature measurement.Thirdly, we use a professional pressure measuring sensor called BP300 T to achieve the measurement of blood pressure. According to the basic principle of blood pressure measurement, we have designed the measuring circuit, and used amplitude characteristic ratios method to determine systolic and diastolic blood pressure from pulse waves. Meanwhile, considering the inherent connection of blood pressure and pulse, we count the extreme point of pulse wave which is generated in the process of blood measurement. And then, we calculate the frequency of the pulse.Above all, this paper involves electronic-information technology and bio-sensing technology, which is the most cutting-edge study in the 21 st century. It has a significant scientific value and large social prospects. However, as time limited, this paper is only a preliminary design.We only have completed the overall program’s design and realized each module’s simple measurement. There are still many key issues to be solved.