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چكيده انگليسي :

The study of network coding in single hop wireless networks Mashaalah Nazarpour m nazarpour@ec iut ac ir Date of Submission 2011 06 25 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Mehdi Mahdavi m mahdavi@cc iut ac irAbstractNetwork coding is considered by researchers to be one of the most important areas to apply many of thenetwork applications such as broadcasting and multicasting In the existing data networks routers sendpockets in the network through store and forward This way routers save the pockets in the buffer and sendthem to the related link or links after finding the pocket route Through network coding routers are able to dodifferent mathematical functions on the pockets for example they can combine them linearly and then sendthem This has two advantages including the increase in the network capacity and its robustness Networkcoding can reach its maximum capacity either in its broadcasting or multicasting mood More over networkcoding offers more advantages such as reduction in the energy use reduction in the amount of delay reduction in complexity safety Network coding can also be used in wireless networks One of the mostsignificant characteristics of wireless networks which distinguishes it from wired networks is the same mediain this kind of network In fact each forward in the wireless network is a kind of broadcasting Anotherfeature of wireless network is its lossy links in the network Coding can reach its optimal throughput besidesresisting pocket loss This study deals with the issue of broadcasting in a wireless network including centralstation and some receivers All these receivers are connected to the sender through the same channel Thechannel for each receiver is different according to loss rate dependence and independence Time iscategorized in slots and senders can send only one pocket in each single slot In broadcasting mood if apocket from a sender in each slot includes new information it is considered as an optimal throughputmethod In using network coding in live services the decoding delay should be lowered But in general it isimpossible to find a way which has the optimal throughput and the zero amount of decoding delay So a newcoding method is presented whose decoding delay is zero But we should also calculate the amount ofthroughput which is lost using this method This method has some other advantages such as simplicity fewmathematical functions and little queue length which make it a suitable method for live application sensitiveto delay The objective is to see if this optimal throughput can be improved without adding to ARQcomplexity The comparison between the new and the mentioned methods is done through simulation Keywords Network Coding Wireless eraser networks Broadcasting Decoding delay

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