The continuous increase in the number of wireless devices and sensors along with the huge demand for higher data rates and limited radio frequency spectrum resources have prompted the need for novel wireless communications technologies with improved radio frequency spectrum sharing features. Recent radio spectrum measurements have corroborated the fact that the radio spectrum is being used inefficiently; and consequently, the concept of cognitive radio has been proposed as a promising approach for the efficient utilization of the radio frequency spectrum. A cognitive radio represents a communication system equipped with the abilities to learn its surrounding environment through sensing and measurements and to adapt its features for a better utilization of existing radio frequency spectrum resources with the aim of securing communications links with adequate quality of service. This proposal addresses several important problems that must be overcome before cognitive radio systems can be implemented in practice. These challenges include the design of circuits with adequate precision for processing of the received signals, the design of fast and computationally efficient ways to sense the occupancy of the spectrum and the design and analysis of multiple access schemes that will permit many users to share the spectrum without causing undue interference to each other. This project will use innovative techniques to solve these challenges thereby enabling a better utilization of the available radio spectrum resources. Applications of the proposed work include radio astronomy, communication networks, smart grids, wireless sensing and monitoring devices, remote monitoring of earth, and telemedicine.
This project will design interference-resilient orthogonal frequency division multiplexing based cognitive networks and optimize their performance for better utilization of the radio frequency spectrum. The objective is to develop transformative solutions and approaches by unveiling and exploiting cross-disciplinary concepts and results from mixed analog/digital signal processing, fast spectrum sensing, computational statistics and stochastic geometry with significant impact to both theory and practice. Successful completion of this project holds the potential to advance the state-of-the-art knowledge and understanding in the deployment and optimization of spectrum sharing communications networks. This project will develop new algorithms and methodologies to optimize the design of a radio frequency front-end and analog-to-digital converters in the presence of primary user interference, and multiple-access schemes to mitigate secondary user interference. This project will also contribute to the development of large-scale simulation and computational methods for enhancing the operation of cognitive wireless communications networks. The proposed research work will be integrated with the educational mission through the development of innovative pedagogical practices, advising of students, active recruitment of domestic students and students from under-represented groups. These efforts will dovetail with the ambitious 25 by 25 growth plan at Texas A&M University, which seeks to increase the enrollment in the College of Engineering to 25,000 students by 2025, thereby increasing access to high quality education.
