Coexistence of heterogeneous wireless networks (HWNs) to provide ubiquitous service is an inevitable trend. Vertical Handoffs (VHOs) are crucial requirements for convergence of different access technologies. In this paper, a utility-based VHO decision algorithm is proposed. A profit function is used to calculate the profits gained from a VHO and to select the target network accordingly. Signaling overhead, handoff delay and load of network is used to model loss function when a VHO occurs. The VHO algorithm and trigger rules of this paper are proportional to optimize the utilization of radio resource. Simulation results present that our proposal gains lower blocking rate, dropping rate, handoff times and higher throughput. And user satisfaction is improved.
Keywords-vertical handoff decision; heterogenerous wireless network; utility; blocking rate; dropping rate; user satisfaction.I.