Scheduling wireless links by graph multicoloring in the physical interference model

Abstract: Scheduling wireless links for simultaneous activation in such a way that all transmissions are successfully decoded at the receivers and moreover network capacity is maximized is a computationally hard problem. Usually it is tackled by heuristics whose output is a sequence of time slots in which every link appears in exactly one time slot. Such approaches can be interpreted as the coloring of a graph's vertices so that every vertex gets exactly one color. Here we introduce a new approach that can be viewed as assigning multiple colors to each vertex, so that, in the resulting schedule, every link may appear more than once (though the same number of times for all links). We report on extensive computational experiments, under the physical interference model, revealing substantial gains for a variety of randomly generated networks.