Load balancing call admission control algorithm (CACA) based on soft-handover in 5G Networks

Abstract

Soft-Handover or connected-before-break is a procedure where the user equipment (UE) is always connected to the radio link with no need for synchronization with adjacent cells. Therefore, the user equipment (UE) is connected softly with more than one NodeB at the same time. Due to many reasons such as orthogonality in long-term evolution (LTE), which is based on orthogonal frequency division multiplexing (OFDM), soft-handover is not supported by fourth-generation (4G) systems. On the other hand, 5G systems can support seamless soft-handover between the original cell and neighboring cells. To guarantee a seamless handover in 5G systems with an acceptable quality of service (QoS) for end-users, an intelligent call admission control (CACA) algorithm should be provided. Therefore, a new multi-cell CACA is 5G systems is presented in this paper. The presented CACA is taken into consideration the “cell breathing” phenomena that cause the overloaded cell coverage to shrink. The admission of the user is based on a minimum bit rate to be achieved, a maximum distance from the base station, and a maximum number of active users in the cell. Considering different interference factor values, the presented numerical results reveal the effectiveness of the suggested CACA in balancing the load over the whole network by transferring the traffic from overloaded cells to the neighboring cells with less load, and hence, the overall network performance is improved. To validate the effectiveness of the CACA, some comparative results are shown with and without applying the proposed CACA.