شبكه هاي حسگر بدني و ارائه روشي براي كاهش مصرف انرژي در آنها

چكيده انگليسي :

Body Area Sensor Networks and a Method to Improve Their Lifetime Aida Ehyaie aehyaie@ec iut ac ir Date of Submission 29 Apr 2009 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisors M R Hashemi hashemim@cc iut ac ir P Khadivi pkhadivi@ec iut ac irAbstract Progress in medicine has extensive relation with the other fields of science and technology The thorougheffect of the development of various sciences on human life and presenting healthcare services shows thisrelation Emersion of Body Area Sensor Networks BASN is one of these advances Wireless body area sensornetworks will revolutionize health care services by remote continuous and non invasive monitoring Hence it sexpected that preventing and early detecting of diseases will be added to the current healthcare systems which aremostly based on disease management and not on health management BASN is one of the important applications of Wireless sensor networks WSNs which are one of the mostfascinating results of recent advances in multiple branches of technology such as wireless systems networking microelectronics and sensor design Body area sensor network is a network of biomedical sensor nodes whichare placed carefully over the human body or implemented inside of it to provide real time reliable and longlasting health monitoring BASNs should monitor different physiological parameters of a person for a long periodof time Due to finite energy budget of sensor nodes efficient energy usage is essential in order to provide a longlife time for the network Though this is one of the most important challenges in BASNs In this thesis after introducing BASNs and their influence on the modern medicine the state of the art of thistechnology is reviewed Moreover we investigate the challenge of energy in these networks and propose amethod to improve life time of the sensors This solution includes employing a relay network in addition to thenetwork of body sensors to reduce energy consumption of sensor nodes when transmitting data to the sink Theuse of the relay network in conjunction with body area sensor networks decreases the depletion rate of energy inthe sensor nodes Hence the most part of the communication is performed by the relay nodes in a multihoparrangement and the sensor nodes transmit over short ranges with no relaying The results show significant raisein sensors life time compared to either single hop or multihop transmission Furthermore the total energy usageof the network is reduced considerably compared to the single hop communication case due to substitution of allfar field transmissions by near field ones Based on the original topology of BSN total energy consumption ofBSN plus relay network can be much less than multihop communication Placement of relay nodes is an optimization problem which is studied in this report This problem has beeninvestigated in wireless sensor networks however considering the special requisites of body area sensornetworks we try to solve this problem for these networks Two separate algorithms DCover and SMT MSPBEL are used to address this problem We propose an algorithm for DCover problem which has less complexity andsmaller number of relay nodes Moreover we show that in two special cases of transmission ranges of sensors andrelay nodes the algorithm will be much simpler and the required number of relay nodes will be smaller Key WordsBody Sensor Network Relay Network Relay Node Placement Relay Node Sensor Node

احيايي، آيدا

شبكه هاي حسگر بدني و ارائه روشي براي كاهش مصرف انرژي در آنها

شبكه رله , جايگذاري گره هاي رله , گره حسگر , گره رله , BSN