Design For Heterogeneous Data Wireless Body Area Network Energy Efficient MAC Protocol

In the research of wireless sensor networks,the body area network is one of the major trends in the development of today.It has a broad market prospect in the field of telemedicine and health care.Wireless body area network(WBAN,Wireless Body Area Network)is composed of a series of low power consumption,miniaturization,lightweight,can form in the surface of the body or implanted in the human body,can provide real-time data,with wireless communication capacity of the sensor nodes of the network,has a very good prospect in the field of medical,military,sports and entertainment etc..Wireless body area network and traditional wireless sensor networks have great difference.WBAN sensor nodes are usually powered by the battery,its energy is very limited,especially for the implantation of the sensor inside the human body is not easy to replace the battery and charging.Therefore,how to reduce the power consumption of nodes and prolong the network lifetime has become the primary goal of WBAN.In wireless body area network(WBAN),MAC(Media Access Control,MAC)protocol control sensor nodes use wireless channels to allocate wireless channel resources to nodes,which has a great impact on the performance of wireless sensor networks.The design of an energy efficient MAC protocol,it has a great practical significance for improving performance of WBAN.This paper introduces the research background,current situation,significance and challenges of WBAN.The system architecture,characteristics and key technologies of WBAN are analyzed,and the energy saving strategy of WBAN is summarized.This paper focuses on the analysis of the MAC layer access protocol,and analyzes the main causes of the energy consumption of the MAC layer.The existing MAC protocols are classified and summarized,and the typical MAC protocols are analyzed and compared.The IEEE 802.15.4 MAC layer protocol is described in detail.In WBAN,different traffic generated by the sensor has different QoS requirements in the transmission.According to the characteristics of these heterogeneous data,the wireless sensor network node is heterogeneous.According to the characteristics of heterogeneous data,a high efficiency and energy saving MAC protocol based on priority is proposed.In order to guarantee the priority of data transmission,the data is divided into 5 different levels.This protocol improves the frame structure,the first stage in the CFP slot into a mini slot,the mini slot is to ensure that emergency request packets in an efficient way to send to coordinator.Secondly,an efficient algorithm is proposed to seize the time slots for high priority packet transmission.This paper introduces the protocol operation process,priority backoff strategy,time slot allocation strategy,Emergency service processing and time slot preemption strategy.In this paper,the P-MAC protocol is improved in the aspects of priority assignment,time slot allocation and emergency service processing,which satisfies the requirements of wireless sensor network node communication.In this paper,based on the OMNeT++ simulation platform,a priority based MAC protocol is simulated,select the IEEE802.15.4 MAC protocol and the McMAC protocol proposed by scholars are compared.The results show that the high efficiency MAC protocol based on priority has some advantages in network energy consumption,data transmission delay,protocol operation overhead and data transmission efficiency.