Energy Optimization of Scheduling and Packet Loss in Wireless Sensor Networks

Sammanfattning: We study the data aggregation of Wireless SensorNetworks (WSN). This is done by considering two problemformulations. The problems examine two different parts of thenetworks and their impact on its energy consumption. The firstproblem looks at the impact of packet loss and the secondproblem on the impact of network scheduling. The reason behindthis is that WSN usually operate on battery power and may beplaced in locations where they are hard to replace. Thus if itis possible to reduce the energy consumption of a WSN, thetotal lifespan of it will be increased. This led to the formulationof a NP-hard deadline constraint problem that is solved bysimulation. For simulation purposes a fixed tree topology wasused to investigate the impact of packet loss rate. The simulationsof the seven different scheduling policies use the same tree. Itcould be concluded from this that an increase in packet lossby only 12% percent leads to two times as long transmissiontime and therefore also twice the energy consumption. For thesecond problem the scheduling policies are evaluated by theirspeed, reliability and evenness and assigned an index based onthese parameters. Here we could see that clear improvementscould be done to a system depending on which parameters wereprioritized.