Committee:

Dr. Gee-Kung Chang, ECE, Chair , Advisor

Dr. John Barry, ECE

Dr. Xiaoli Ma, ECE

Dr. Biing-Hwang Juang, ECE

Dr. Umakishore Ramachandran, CS

Abstract:

The objective of the proposed research is to study methods that improve reception quality and mitigate interference in millimeter-wave wireless communications for small-cell coverage in heterogeneous networks. Millimeter-wave bands provide sufficient spectral resource and avoid cross-tier interference with existing low-frequency wireless services in a heterogeneous network. However, coordination over millimeter-wave small cells for combating interference, providing line-of-sight links, and improving system efficiency has stringent requirements on synchronizations and backhaul capacity. As a result, current standards and approaches for the coordination of low-frequency cells based on distributed digital processing can barely apply on millimeter-wave small cells. This work theoretically and experimentally explores new directions of inter-cell interference cancellation and coordinated multi-point transmissions for coordination over millimeter-wave small cells. Different from conventional approaches, the millimeter-wave coordination mechanisms studied in this research are inherent from a fiber-wireless architecture that enables optical processing for millimeter-wave generation, distribution, synchronization, and centralized coordination. Based on the supportive results derived from the preliminary study of the mechanisms, we propose the methods of cooperative multiple-input multiple-output and network-wide coordination based on optical processing and fiber-wireless centralization for multi-cell and multi-user coordination over millimeter-wave small cells. The proposed methods utilize centralized resource and local high-capacity fiber links and are expected to provide transparency and global coherency for efficient coordination and seamless integration with future heterogeneous networks.