Title:  Ultra-Massive MIMO Communications in the Millimeter Wave and Terahertz Band

Committee: 

Dr. Akyildiz, Advisor    

Dr. Li, Chair

Dr. Sivakumar

Abstract:

The objective of the proposed research is to enable the ultra-massive multiple-input multiple-output (UM MIMO) communication system in the millimeter wave (mm-wave) and terahertz (THz) band wireless networks. The mm-wave and THz band communications are envisioned as key wireless technologies to satisfy the demand for throughput in the 5G and beyond eras. The very large available bandwidth in this ultra-broadband frequency range comes at the cost of a very high propagation loss, which combined with the low power of transceivers, limits the communication distance and data rates. Therefore, we adopt the UM MIMO communication technique to solve these issues. In this proposal, first, channel estimation at mm-wave and THz band is conducted under the utilization of large-scale antenna arrays. In particular, due to the channel's nonlinearity and computation complexity yielded by traditional channel estimators, a nonlinear approach in deep learning is applied to efficiently solve for the estimation challenge. Second, based on the knowledge we obtained from channel modeling and estimation, we demonstrate that the mm-wave and THz band communications can enable realistic applications in both terrestrial and satellite communication scenarios.  Owing to the advantage of the abundant spectrum resources at such bands, feasible communication links can be established in low-Earth orbits on CubeSats to form a paradigm of Internet of Space Things. A new resource allocation scheme based on deep learning is proposed to support the multi-band communication in inter-satellite links. Third, with the advances in graphene and other 2D materials, the mm-wave and THz band can be used in constructing large intelligent communication environments to further exploit the temporal and spatial diversity, as well as control the propagation of electromagnetic waves in an unprecedented manner, including anomalous reflection, absorption, and conduction.