Coding theoretic methods for systems with side information

In real life, many communication system problems have side information due to the broadcasting nature of communication medium. By utilizing the side information, either the communication rate can be increased or the cost of transmission can be decreased. In this proposal, I am going to investigate three problems: index-coded retransmission for OFDMA downlink, decentralized framework for coded caching, and key generation using physically unclonable functions (PUFs). In the first part, we propose a novel index-coded retransmission scheme for OFDMA downlink. In OFDMA downlink, receivers can often decode the other users’ physical layer signals on the other sub-channels, which can be exploited as side information to cancel the interference in subsequent retrans- mission. In contrast to the original index coding formulation, its application to wireless networks has to deal with decoding error probabilities due to channel variations such as fading. We show the tradeoff between the transmission rate gain and the performance of index coding algorithm. We simulate the end to end system with a novel randomized greedy coloring index coding algorithm, and show non-trivial gain with a 100 nodes system. In the second part, we shift to the problem of coded caching: in this case instead of storing a whole file as side information, we can design the cache content to minimize the worst case transmission rate. We propose a novel framework that can translate any centralized coded caching scheme to decentralized scheme without transmission gain loss. We prove the performance of our algorithm is not degraded due to the dynamics introduced by decentralization. In the third part, we present an algebraic binning based coding scheme and its associated achievable rate for key generation using physically unclonable functions is determined. This achievable rate is shown to be optimal under the generated-secret (GS) model for PUFs. Furthermore, a polar code based polynomial-time encoding and decoding scheme that achieves this rate is also presented.Electrical and Computer Engineerin