NeTS: Medium: Implications of Receiver RF Front End Nonlinearity on Network Performance: Fundamentals, Limitations, and Management Strategies

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

Since the introduction of cell phones, the demand on mobile data traffic has been continuously growing. The efficient utilization of the radio frequency spectrum and clever wireless network management are key for satisfying this traffic demand and spurring economic growth. It has been shown that spectrum can be more efficiently used when shared among users rather than licensed to specific users and communication systems. However, spectrum sharing technology and regulations are still in their infancy. In particular, the effect of radio receiver performance on spectrum regulation and management is not well understood and needs careful analysis, both theoretical and experimental. This project will derive the fundamental concepts and management strategies to educate students, researchers, regulators, standardization bodies and industry about the importance of characterizing receivers for a successful realization of dynamic spectrum access systems. The results of this research will increase social awareness about low-quality wireless devices and their implications on capacity and serve as an important step towards the healthy obsolescence of bad receivers from the market. This project aims to redefine the way we understand, design, and optimize the next generation wireless networks, which will have far reaching economic and social benefits. Radio frequency (RF) receiver front ends are nonlinear systems that create inter-modulation distortion and, hence, can impair receiver performance by creating harmful cross-channel interference in non- intuitive ways. The need to better account for adjacent channel interference on network performance becomes indispensable with the advent of spectrum sharing between heterogeneous wireless systems, and for communication systems which exhibit poor selectivity, such as millimeter wave technology. This project addresses the technological challenges in receiver-centric wireless network design and management by providing a fundamental analysis that quantifies the implications of RF front end non-linearity on network performance, utilization, and fairness. The scientific merit of this project is to (1) derive fundamental models and metrics that characterize and quantify the implications of RF front ends on network performance; (2) develop a comprehensive wireless network management framework and strategies that account for the RF imperfections, transmit masks, and diversity of heterogeneous wireless devices; (3) establish fundamentals of nonlinear interference between symbols of adjacent channels for network-level nonlinear interference avoidance and cancellation; and (4) build a testbed for the validation of theoretical concepts. This testbed will enable further research and education beyond the project period and, together with the analytical framework, initiate the much-needed research on RF front end non-linearity-aware network design and management for high-performance next generation wireless networks.