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Because of the many-to-one nature of wireless sensor networks (WSNs), the topology of WSNs is called a sink tree. In this thesis we try to reduce interference in WSNs by using topology control to build a sink tree with high throughput. Topology control can decrease the interference level of an ad hoc network by replacing high interference links with lower interference paths. However, there is not any discussion about the consequences of transmitting data via long paths, especially in a tree base network. We discuss the impacts of long paths on the sink tree, different metrics measuring interference, and methods that aim to increase the throughput of the sink tree.
We present Least Transmission Path (LTP), a locally computed topology control algorithm that has two goals: it minimizes the interference in the sink tree according our metric, and raises throughput of the sink tree. In our algorithm, sensor nodes have little knowledge about the information of the network, such as location, shortest path to the sink and so on, in advance. The results of our analysis reveal that interference decreases and throughput increases in the sink tree. Moreover, our algorithm allows the sink to receive more packets from distant nodes.

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