Dynamic Reuse of Unlicensed Spectrum: An Inter-Working of LTE and WiFi

摘要

The dynamic exploitation of unlicensed spectrum by mobile operators is becoming a trend of future 5G networks, with several efficient solutions being standardized for enabling spectrum sharing. Solutions with various design philosophies diversify the network architectures and protocols. Among them, LAA aims at the physical-layer coexistence of LTE and WiFi within the unlicensed spectrum, while LWA and LWIP focus on aggregating the link capacity of LTE in the licensed spectrum and WiFi in the unlicensed one. In this article, a comprehensive survey of these three spectrum sharing technologies are provided. Moreover, a novel analytical framework is proposed to evaluate the network performance of these technologies by incorporating both spatial and time domain analyses and integrating different types of cells in one network as a whole. Simulation results are provided to compare the system throughput of these spectrum reuse technologies.