This project aims at developing a MIMO-aware Cooperative Dynamic Spectrum Access framework, termed McDysa, which enables multiple primary users and multiple secondary users to cooperate in dynamic spectrum sharing and to exploit underlying cognitive radio and MIMO techniques for significant spectrum efficiency gains and physical layer security enhancement. The proposed research is centered on three thrusts: relay selection and resource sharing in McDysa, achievable transmission capacity analysis in McDysa, and secrecy capacity enhancement in McDysa.

Intellectual Merit:

The following research activities were carried out during the course of this three-year project: i) developing a MIMO-based cooperative Dynamic Spectrum Access (DSA) framework that enables multiple primary and multiple secondary users to cooperate in dynamic spectrum sharing and to exploit the underlying cognitive radio and MIMO techniques to achieve significant performance gains; ii) proposing a cooperative wireless infrastructure and spectrum leasing framework for sharing unused TV spectrum, in which the ownership of network infrastructure and spectrum is decoupled, and each can be leased and delivered as a service on demand; iii) investigating cooperative jamming for secure communications in MIMO cooperative cognitive radio networks (MIMO-CCRNs) by jointing considering beamforming and power allocation, and jointly considering energy and information cooperation; iv) exploring optimal stopping theory based jammer selection for securing cooperative cognitive radio networks; v) jointly designing jammer selection and beamforming for securing MIMO cooperative cognitive radio networks; vi) conducting theoretical analysis of secrecy transmission capacity in wireless in wireless ad hoc networks; and vii) proposing robust secrecy transmission algorithms that can be applied to various scenarios with different security requirements in a two-tier 5G heterogeneous network, where the macro base stations at the macrocell tier are equipped with massive multiple-input multiple-output to provide space diversity and the local base stations at the local cell tier adopt non-orthogonal multiple access to accommodate dense local users. One can see that the PIs have tackled novel problems and achieved important results toward cooperative communications with dynamic spectrum sharing and MIMO techniques for significant spectrum efficiency gains and physical layer security enhancement.

Broader Impact:

The project was carried out by the PI and the co-PI who are female faculty members and a few graduate students at the George Washington University, yielding a number of peer-reviewed publications in prestigious journals and conference venues. The PIs organized weekly group seminars open to all graduate students focusing on cognitive radio networking and MIMO-enabled cooperative communications in the past few years, and the research findings of this project were integrated into the courses of wireless and mobile security via course projects and lecture presentations. The project can provide regulatory bodies such as FCC, with rigorously proven, efficient solutions that can serve as guidelines and backbone for promoting and establishing more flexible spectrum access policies and regulations. It also offers technical and scientific solutions to the problem of shortage supply in spectrum. This enables the general public with high-speed and concurrent access to public information, such as library, hospitals, and schools. Our research findings were disseminated to the relevant audience through high-quality publications as well as presentations in focused workshops and conferences.

Last Modified: 01/27/2019
Modified by: Xiuzhen Cheng