Earticle

The paper proposes a vertical handoff algorithm based on differential pre-decision and improved utility-function method. This algorithm is relied on utility function to improve its two parameters, which are received signal strength and bandwidth, by using their normalized values to determine the target network. Then, it enters judgment stage of vertical handoff, where introduce differential prediction algorithm that has good accuracy to further constraint the switching decision through taking a prediction of the RSS into account. The purpose is to reduce the impact of ping-pong effect and to obtain accurate handoff. The paper applies MATLAB software to gain the simulated analysis based on this algorithm, And compares the performance of this switching algorithm with utility function algorithm to demonstrate its priority. Simulation results shows that the proposed algorithm can significantly reduce the impact of the ping-pong effect and improve the switching efficiency and the system performance as well in heterogeneous network environments.