A vertical handoff decision scheme using subjective-objective weighting and grey relational analysis in cognitive heterogeneous networks

With the limitation and low utilization rate of spectrum resources, how to maintain the best continuous network connection for user while reducing the total number of handoff has become an urgent problem to be solved in the handoff decision of cognitive heterogeneous networks. Therefore, a cognitive heterogeneous network vertical handoff decision scheme combining subjective-objective weighting and grey relational analysis (GRA) is proposed. Firstly, an agent-based decision-making framework is proposed based on the review of relevant literature; secondly, the attributes weighting algorithm combining subjective-objective weighting is proposed; thirdly, the steps of analytic hierarchy process (AHP), entropy weighting method, and GRA method are analyzed in detail; then an example is given to analyze the proposed algorithm in single decision point, and the performance of the proposed algorithm is compared with that of three similar multi-attribute decision making (MADM) algorithms; lastly, some problems and challenges of the existing vertical handoff MADM decision-making algorithm are discussed, and the future research directions are proposed. Simulation results show that the proposed method is effective in reducing the total handoff number and ranking anomaly rate.