CAREER: The Design of Resource-Efficient Communications Systems by Combining Decision Feedback with Error-Control Coding

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

The ubiquity of communications technology is becoming more evident every day. As the number of customers grows within each market, along with their demand for higher and higher data rates, the need to use available resources such as power and bandwidth as efficiently as possible becomes paramount. Typically a communications system that is operating near theoretical limits requires a receiver whose computational complexity is prohibitively large. To reduce complexity, it is common to linearize a portion of the receiver but this can severely reduce system performance relative to theoretical potential. However, there is a class of nonlinear receivers known as decision-feedback receivers whose complexity is essentially no more than that of linear receivers but whose performance is often much closer to that of optimal receivers. This research explores the decision-feedback receiver structure as a practical means of realizing resource-efficient communications systems. The research is also integrated into educational activities at all student levels. Aspects of the research are purposefully introduced to undergraduate students in the classroom, during summer work programs, and through senior-level thesis advising. This prepares them both technically and motivationally to enter industry or to pursue further studies in graduate school. Graduate students are provided an environment conducive to doing quality research in the exciting field of communications, whether they choose careers in industry or academia. The technical aspects of the research involve three components. First, it is determined, at least in principle, how to combine a decision-feedback receiver with error-control coding for a variety of important communications channels. Then, within these decision-feedback frameworks analytical relationships between available resources and system requirements are derived, and resource-efficient systems are designed. Lastly, the transition is made from theoretical random codes to actual encoders and decoders that are simulated in software. Together these investigations provide communications systems that are highly efficient in regard to their conservation of resources, yet with low enough complexity to be amenable to implementation.