Abstract

The rapidly increasing demand in indoor smallcell networks has given rise to the concept of local beyond 5G (B5G) operator (OP) for local service delivery. The local B5G OP aims to provide wireless network using licensed subbands in an indoor area and tries to gain profits by renting out the infrastructure to the mobile network operators (MNOs). With local B5G OP deployment, the quality of service (QoS) can be guaranteed at mobile broadband users (UEs) and smart devices, i.e., machine type communications (MTC) and ultra reliable low latency (uRLLC). In this paper, we consider the scenario that the local B5G OP aims to maximize profit by optimizing its infrastructure rental fee while renting out cache-enabled smallcell base stations (SBSs) to the MNOs. Each MNO tries to minimize the cache intensity subject to latency constraint at mobile UE. The concept of infrastructure sharing is also deployed at the local B5G OP such that multiple MNOs can utilize the same cache-enabled SBSs simultaneously and the local B5G OP will cache the popular files according to the MNO’s largest demand. The optimization problems of the local B5G OP and the MNOs can be transformed into geometric programming problems. Then, we show that the Stackelberg equilibrium is obtained through successive geometric programming (SGP) method. Lastly, we perform an extensive performance evaluation that reveals interesting insights including the optimal SBS intensity that MNOs should rent from the local B5G OP as to satisfy end-to-end latency, 10 ^-3 sec, of data transmission from each SBS to UE. The optimal price of renting out infrastructure for the local B5G OP at the Stackelberg equilibrium is also illustrated.