A strong converse theorem for channel capacity establishes that the error probability in any communication scheme for a given channel necessarily tends to one if the rate of communication exceeds the channel’s capacity. Establishing such a theorem for the quantum capacity of degradable channels has been an elusive task, with the strongest progress so far being a so-called “pretty strong convers...

THE demand for ever larger, more efficient, reliable, and cost effective communication networks is motivating new network architectures, such as ad hoc networks, cognitive radio, relay extensions for cellular networks, sensor networks, and wireless mesh networks. The study of such networks requires a fundamental shift from thinking of a network as a collection of independent communication pipes...

Researchers have proposed formal definitions of quantitative information flow based on information theoretic notions such as the Shannon entropy, the min entropy, the guessing entropy, belief, and channel capacity. This paper investigates the hardness of precisely checking the quantitative information flow of a program according to such definitions. More precisely, we study the “bounding proble...

This paper presents fundamentals of a theory to characterize chaos-based communication. We describe the amount of information a dynamical system is able to transmit, the dynamical channel capacity, which takes into account the information that a dynamical system generates.

Information retrieval is concerned with how to classify information and how to judge the similarity between two objects, such aswritten documents. As the amount of information available in digital formhas grown, so too has theneed for accurate and scalable algorithms for handling this information. Information theory is concerned with the production and transmission of information. Using a frame...

This paper examines extensions by Dretske, Barwise, Seligman and others to the Shannon-Weaver model of information communication, with special reference to geographic information. Classifications of entities into types are taken as the basis for information repositories, while structure-preserving mappins called infomorphism provide the linkages. A key notion is that of a channel, which can be ...

The general problem of estimating the a posteriori probabilities of the states and transitions of a Markov source observed through a discrete memory less channel is considered. The decoding of linear block and convolutional codes to minimize symbol error probability is shown to be a special case of this problem. An optimal decoding algorithm is derived. In information theory, turbo codes (origi...

Preface The reliable transmission of information bearing signals over a noisy communication channel is at the heart of what we call communication. Information theory—founded by Claude E. Shannon in 1948—provides a mathematical framework for the theory of communication; it describes the fundamental limits to how efficiently one can encode information and still be able to recover it with negligib...