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Polar codes, introduced recently by Arikan, are the first family of codes known to achieve capacity of symmetric channels using a low complexity successive cancellation decoder. Although these codes, combined with successive cancellation, are optimal in th ...
We consider a wireless relay network with no channel information, which implements differential distributed space-time coding. We propose a coding strategy based on Cayley codes, which yields high data rate codes available for an arbitrary number of relay ...
The addition of a feedback link to a discrete memoryless channel does not increase its capacity, but it does bring with it other benefits. One of these benefits is an increase to the best achievable error exponent. In the first part of this thesis we revis ...
We consider the compound capacity of polar codes under successive cancellation decoding for a collection of binary-input memoryless output-symmetric channels. By deriving a sequence of upper and lower bounds, we show that in general the compound capacity u ...
This thesis addresses the topic of Low-Density Parity-Check (LDPC) code analysis, both asymptotically and for finite block lengths. Since in general it is a difficult problem to analyze individual code instances, ensemble averages are studied by following ...
In this thesis we study coding strategies for single-user block-fading channels. The block-fading channel is a simplified model of slowly varying wireless communication channels with stringent delay constraints. This model is particularly important in prac ...
Compilation of polymorphic code through type erasure gives compact code but performance on primitive types is significantly hurt. Full specialization gives good performance, but at the cost of increased code size and compilation time. Instead we propose a ...
We consider communication over the binary erasure and the binary additive white gaussian noise channels using fixed linear block codes and also appropriate ensembles of such codes. We show concentration of the magnetization over the channel realizations an ...
This work is concerned with codes, graphs and their links. Graph based codes have recently become very prominent in both information theory literature and practical applications. While most research has centered around their performance under iterative dec ...
We investigate the average erasure probability of the belief propagation algorithm over the binary erasure channel (BEC) for various finite-length low- density parity-check (LDPC) ensembles. In particular, we give tight upper bounds on the "error floor", i ...