Claude Shannon?s ?A Mathematical Theory of Communication? is the landmark event that paved the way for the development of modern communication systems. Shannon analyzed the fundamental redundancy that must be added to data in order to achieve reliable communication in the presence of noise. Since then his vision has guided the practical design of virtually all aspects of modern communication systems such as forward error correction, spectrally-efficient communication, multiuser and inter-symbol interference, multiple-antenna systems, opportunistic communication, and joint compression/transmission. However, while feedback is present in virtually all modern communication systems, the field of information theory has had relatively little impact on how feedback is employed in practice. The proposed work will advance knowledge by developing a more complete understanding of how feedback should be employed in communication systems and what quantitative improvements in delay, complexity, and transmitted power one can expect from its effective use, under realistic delay constraints such as those found in high-speed wireless data. In summary, the successful completion of the project is expected to contribute new mathematical tools, designs, viewpoints, and models to the field of information theory.
The goal of this research is to bring the insight, design guidance, and performance bounds for which information theory is known to bear on the design of systems with feedback. By providing new design principles and feedback codes, this research has the potential not only to advance basic science but also to improve the efficiency and reliability of our communications infrastructure, including consumer technology such as WiFi and smartphones. Given the proliferation of personal communication devices, such improvements would augment the efficiency with which crucial resources such as energy and radio frequency bandwidth are currently utilized.
