Abstract:

The dynamic spectrum access technology can achieve nearoptimal spectrum utilization by allowing cognitive users sense and utilize available spectrum opportunistically. Time overhead and fairness are part of the key evaluation criteria for the spectrum allocation algorithms, and a naive spectrum assignment can lead to significant unfairness and system overhead. In this paper, based on graph coloring model, the evaluation system and optimization goals are established. From the maximal independent set, a novel graph coloring algorithm based on maximum weighted independent set (MWIS) is proposed. Theory and simulation analysis show that through MWIS algorithm we can obtain the nearoptimal total spectrum utility and fairness, and the time overhead for this algorithm is equal to the number of channels, which is far below the CSGC algorithm.

Key words: cognitive radio;spectrum allocation;graph theory;utility;independent set