Distance Two Labeling for Multi-Storey Graphs
More and more Communication networks have been developed, but the available radio frequencies allocated to communications are not sufficient. It is important to find an efficient way to assign these frequencies. The main difficulty is given by inferences caused by unconstrained simultaneous transmissions which will damage communications. The interference can be avoided by means of suitable Channel assignment. In 1980, Hale introduced the Graph theory Model of the channel assignment problem where it was represented as a vertex coloring problem. Vertices on the graph correspond to the radio stations and the edges show the proximity of the stations. In 1991, Roberts proposed a variation of the channel assignment problem in which the FM radio stations were considered either "Close" or "Very Close".