The Research In MAC Protocol Of Wireless Body Area Network Based On The Priority

With the development of sensor technology and wireless networks, people pay more attention to the application of wireless body area network for human body, especially in the medical field. Wireless body area network (wireless body area network, WBAN), it refers to monitor the body physiological parameters (such as temperature, ECG, blood pressure, EMG, heart rate, oxygen concentration, etc.) by a variety of special sensors which is in the human body or on the surface, and then transmits to the remote monitoring center through a wireless network by the central node. It is not only the new health care, disease surveillance solutions, but also the important part of Internet of things.It introduces WBAN structure, characteristics and the relevant standard IEEE 802.15.6 after the research background,the development,medical applic-ation of wireless body area network, and then analyzes MAC super frame structure. Wireless body area network node energy is limited, is difficult to replace, it is very important to reduce node energy consumption and prolong the lifetime of nodes and network. MAC layer protocol is to control channel access, reduce collision while nodes transmit data frame, reduce the retransmission rate and network delay. The target is to ensure the reliability and improve energy efficiency of nodes.Medical applications, data types and amounts of data were significantly different, and data of WBAN are greatly relevant, such as the physical condition of people is abnormal, perhaps blood pressure, body temperature, ECG data are abnormal. In the IEEE802.15.6 MAC layer, there is 2 stochastic access algorithm, CSMA/CA or Slotted ALOHA. This paper,CSMA/CA algorithm is studied, it proposed to set node priority policies, The important human physiological parameters are transmitted firstly, so that they promptly transferred to the control center, not only to avoid waste of energy caused by the collision of data,but also help to diagnose the patient with the key data.By OPNET simulation software, 802.15.6 CSMA/CA protocol is studied and analyzed.According to priority policy, the mechanism is analyzed with Markov chain model, and analyzes the throughput and power consumption performance.At last, the paper conducts a comprehensive summary and presents development prospects of wireless body area network MAC protocol.