A calculation method for handoff rate based on angle mobility model

Mobility model is important for the performance analysis of wireless networks. The paper presents an angle mobility model. Based on the model, the characters of the direction angle for terminal mobility are analyzed and a calculation method for handoff rate is proposed. The theoretical closed-formula is derived for handoff rate in the condition that users´ moving direction is unchanging in the fixed time interval T. It can be clearly demonstrated that the handoff rate is determined by users´ distributed density, moving speed, and cell radius. However, previous techniques calculating handoff rate require knowledge of the distribution of the cell residence times which is difficult to measure. The formulas of handoff rate illustrate that the number of cell´s users is dynamic equilibrium. The simulation results demonstrate the validity of the theoretical analysis for handoff rate.