A Novel Joint Handover and Base Station Sleep mode Algorithm in HetNet

The demand for wireless resources is increasing in high pace. Heterogeneous network (HetNet), which consists of cells with different coverage, e.g., macro cell base stations (BSs) and small cell BSs, is a key solution to address this increased demand. This paper presents a handover (HO) algorithm for BS sleep-wake mode, which reduces the energy consumption in HetNet. In the first phase of the HO algorithm, parameters such as the distance of user equipments (UEs) with their respective BSs, velocities of UEs and their received power strength (RSS) are employed to determine the necessity of HO. This phase, i.e., HO necessity estimation phase (HONEP), helps reducing the unnecessary HOs and consequently save more energy. After HONEP, in the second phase UEs select the new BS based on the average distance of UEs and BSs to which they approach, RSS and average traffic load of BSs which is advertised through beacon signals. A game-theoretic sleep-awake algorithm is executed in parallel to HO algorithm in BSs. System power consumption and BSs’ average traffic load are evaluated by computer simulation. The effect of users mobility on system performance is discussed accordingly.