Beyond 5G: THz-Based Medium Access Protocol for Mobile Heterogeneous Networks

This article presents a network architecture for the next generation of MHNs, where mmW, terahertz, and conventional mW bands coexist, with cost-benefit trade-offs of each type of link. We envision a radically different communication paradigm and outline a MAC protocol design that switches among the aforementioned bands for data transmissions, falling back on the slower link each time for the reverse channel ACKs. The use of the higher-capacity link in the forward direction for data communication and the slower reverse channel for the returning ACKs allows for uninterrupted unidirectional communication and efficient use of the channel. The article discusses the challenges in analyzing and parameter setting for the various features of the protocol, and identifies candidate solutions. A performance evaluation of the approach is undertaken using a realistic scenario of vehicle-to-infrastructure communication enabling data center traffic backhauling. This performance shows that by adopting the proposed MAC protocol data transfer of around 100 Terabits, it is possible for typical vehicle-to-infrastructure contact times.