Minimizing Interference for the Highway Model in Wireless Ad-Hoc and Sensor Networks

Finding a low-interference connected topology is one of the fundamental problems in wireless ad-hoc and sensor networks. The receiver-centric interference on a node is the number of other nodes whose transmission ranges cover the node. The problem of reducing interference through adjusting the nodes' transmission ranges in a connected network can be formulated as that of connecting the nodes by a spanning tree while minimizing interference. In this paper, we study minimization of the average interference and the maximum interference for the high-way model, where all the nodes are arbitrarily distributed on a line. Two exact algorithms are proposed. One constructs the optimal topology that minimizes the average interference among all the nodes in polynomial time, O(n(3)Delta(3))(,) where n is the number of nodes and Delta is the maximum node degree. The other algorithm constructs the optimal topology that minimizes the maximum interference in sub-exponential time, O(n(3)Delta(O(k))), where k = O(root Delta) is the minimum maximum interference.