Patent ID: 8175016
Filing Date: 2012-05-08
Classification: H04L,H04W,Y02D

Abstract:
1. A method for minimizing an energy cost within a wireless network having a plurality of nodes, including a plurality of transmitting nodes and a plurality of receiving nodes, comprising: determining an energy cost of a gathering of data from a plurality of nodes u to a single node v, wherein the energy cost includes at least an overhearing cost, the overhearing cost consisting of an unnecessary expenditure of energy by unintended receiving nodes receiving redundant information; adjusting a transmission power assignment of a transmitting node; and repeating the determining and adjusting to reduce a total energy cost, wherein determining the energy cost further comprises determining a directed minimum-cost in-arborescence rooted at node v; and wherein determining the directed minimum-cost in-arborescence comprises: constructing a directed graph of the network, wherein the weight of each edge in the graph corresponds to the energy cost; reversing the direction of each edge in the graph; reversing the sign of the weight for each edge in the graph; removing all incoming edges from node v; determining the maximum-cost out-arborescence rooted at node v; reversing the direction of each edge in the arborescence; and reversing the sign of the weight for each edge in the arborescence.