This paper proposes a cell selection scheme that reduces the HO rate in order to minimize the handover delay of carrier aggregation techniques in 5G NSA and LTE-A heterogeneous networks. In order to solve the throughput loss caused by reducing the HO ...
This paper proposes a cell selection scheme that reduces the HO rate in order to minimize the handover delay of carrier aggregation techniques in 5G NSA and LTE-A heterogeneous networks. In order to solve the throughput loss caused by reducing the HO rate, this paper contains a scheme of optimizing HO by adjusting the number of secondary cells (SCell) which additionally connects to the primary cell (PCell) in the CA technology.
In order to propose a CA cell selection scheme for HO optimization in the 5G NSA and LTE-A HetNet environment, the analysis was conducted based on the LTE-A environment. The reason for choosing the LTE-A environment among the various wireless network protocols is that the LTE-A environment is analyzed and modeled through various studies, unlike the 5G NR environment currently under discussion. The HetNet environment is expected to become denser in order to cope with increasing mobile traffic. In a dense network environment, as UE moves, HO occurs frequently and HO delay becomes longer. HO signalling and radio link switching occur during HO delay, therefore data transmission is interrupted. The loss of throughput due to this HO delay is expected to be further intensified in CA technology. If the CA technology is used, the SCell will have an additional activation delay in addition to the HO delay whenever the HO occurs for the PCell connected to the UE. The greater the number of connected SCell, the greater the reduction of throughput due to HO delay. However, minimizing the HO rate to reduce HO delay also results in loss of throughput. When the HO rate is reduced, the UE does not connect to the base station (BS) having the strongest signal strength but maintains the connection with the current BS. Throughput loss can be compensated through the connection of multiple SCells. Therefore, this paper proposes HO optimization through CA cell selection scheme which guarantees throughput while decreasing HO delay.
Previous studies have reduced HO rate by omitting HO based on geographic information, but this study decreases the HO rate based on received signal strength. It differs from previous studies in that it is based on the standardized HO procedure. Also, unlike previous studies of HO in the environment where CA technology is not used, this paper suggests a model to optimize HO by analyzing the effect of HO on CA technology. A CA cell selection scheme for optimized HO is proposed and analyzed. It is confirmed that the cell selection scheme proposed in this study guarantees throughput while reducing HO delay.