An adaptive network selection scheme based on the combination of user mobility and traffic load

The integration of cellular and wireless local area networks (WLAN) has drawn much attention due to their complementary characteristics. Cellular supports wider coverage and better capability to mobile user but with lower bandwidth whereas WLAN have higher bandwidth and lower cost but is effective only in small areas. Based on the combination of users' mobility and network load, this paper proposes an adaptive network selection scheme, called as DMMT (Dynamic Match of Mobility Threshold) scheme. By considering the distribution of the whole users' movement character and arrival rate, we can get the Mobility Threshold (MT) from the solution of optimization problem, which minimize the global network blocking probability. Then we use MT to differentiate mobile users to access different network. To obtain the parameters in the optimization problem, we use the prediction of arrival and mobility characteristics. The heterogeneous networks adjust the MT to adapt to the variation of environment. Simulation results show that the proposed DMMT scheme can reduce call blocking and handoff probabilities compared to the referenced schemes.