Research On Energy Efficiency Optimization Methods For Wireless Body Area Network

In recent years, with the development of information and technology, wirelesssensor network applications dabble in a variety of fields. As one of these importantapplications, wireless body area network (WBAN) which is applied to the field ofmedical and healthcare attracts more and more attentions. WBAN is composed ofwireless sensor nodes which are attached to the human body and a coordinator. Thesensor nodes collect human’s physiological signals and transfer them to the coordinatorwhich has a certain computing capabilities such as personal digital assistant andtelephone and so on and then the coordinator transfers the data to the handling system inhospital via the mobile network. Since the sensor node’s energy is extremely limited, itis a key issue to improve the energy efficiency of WBAN.According to the characteristics of the wireless body area network, we make aresearch on the resource allocation methods. The mathematical model of resourceallocation which is solved subsequently in WBAN is established. The major works inthis paper are in the following:Firstly, research on system model of WBAN. The system model which includesthe topology, channel path loss model and the operating mode are studied and analyzedwhich is the background of the thesis. And then we introduce the convex optimizationproblem and its solver (CVX) briefly.Secondly, network global energy minimization model of WBAN. Under thebackground of the network structure and the transmission characteristics of medicalmonitoring, from the perspective of resource allocation, we optimize the allocation oftransmission power (transmit rate) and transmission time simultaneously from theperspective of resource allocation in WBAN. Finally, the total energy minimizationmodel is established which is proved to be a geometric programming. After that, we canachieve the optimal results and the energy efficiency of WBAN is improvedaccordingly.Thirdly, network lifetime maximization model of WBAN. Based on the totalenergy minimization model and the business characteristics of WBAN, we propose thenetwork lifetime maximization model and prove that it is also a geometric programming.According to the simulation, we can conclude that energy efficiency can be obviouslypromoted by the proposed methods.