Energy Efficiency Analysis Of Wireless Body Area Network Based On HARQ

With the global population aging, more and more people began to pay attention to medical care and medical monitoring, but due to the limited medical resources to monitor changes and make corresponding emergency measures has become a serious problem in the health of the elderly. Therefore, it is important to have the wearable medical equipment for solving the above problems, and the wireless body area network(Wireless Body Area Network, WBAN) has become one of hot questions and there are many devices for detecting peoples' health in the market. The detection technology is gradually mature. IEEE 802.15.6 standard about wireless body area network has been officially released in February 2012.Different from the wireless sensor network(Wireless Sensor Network, WSN), WBAN takes the human body as the network center, the sensor nodes distributes on the body surface or inside the body. The wireless communication between sensor nodes always affected by the human body environment. The same as WSN is that both of the nodes are powered by the battery, in order to be used for a long time, we must save nodes' energy consumption, control the power of the network energy consumption and extend the network life, which has become the research focus of WBAN. Because the nodes in wireless body area network are easy to be affected by human body environment, communication reliability will become unstable. Therefore, we make a deep research on the hybrid automatic repeat request which combined the automatic repeat request and forward error correction.First, we analyzed the characteristics of wireless body area network by consulting a large number of literature data and the importance of error technology on wireless body area network and summarized the existing domestic and foreign research in this field.Second, The IEEE 802.15.6 standard had been outlined. We gave a brief introduction about network structure and applications and narrow band physical layer technology in the paper.Third, the error control technology was introduced in this paper. Such as the automatic repeat request(Automatic Repeat Request,ARQ) technology, forward error correction(Forward Error Correction, FEC) technology and hybrid automatic repeat request(Hybrid Automatic Repeat Request,HARQ) technology. The energy efficiency of wireless body area network based on ARQ, FEC and HARQ was analyzed. According to the characteristics of the adaptive error control scheme for wireless body area network, the Chase merging technology was applied to the HARQ technology, which is a kind of error control mechanism which can meet the requirements of the adaptive coding in wireless domain. In this paper, we analyzed the energy efficiency of HARQ based on different packet length, different repeat times and different error correction values. Besides, the energy efficiency of ARQ, FEC and HARQ were compared and analyzed.