Cost-Reliability Tradeoff in Licensed and Unlicensed Spectra Interoperable Networks with Guaranteed User Data Rate Requirements

Unlicensed spectra access holds the promise of alleviating licensed spectra scarcity and providing super high-rate mobile data services, which has been viewed as one of the key technologies of fifth generation (5G) cellular networks. In this paper, we first design a framework for 5G licensed and unlicensed spectra interoperable networks based on the cloud radio access network technology and the control/data decoupled architecture. Then, we investigate network-level cost-reliability tradeoff from two aspects. First, we study a fundamental tradeoff between the cost and the reliability by minimizing cost for a given reliability level. Second, we define a quality of experience efficiency utility as the complementary measure to characterize the cost and the reliability, offering an inherent tradeoff between them. Moreover, an interference power estimation method is proposed to more accurately estimate channel states to guarantee resource allocation effectiveness. Finally, we conduct extensive simulation study and demonstrate the effectiveness of the interference power estimation method.