Efficient Universal Noiseless Source Codes

Although the existence of universal noiseless variable-rate codes for the class of discrete stationary ergodic sources has previously been established, very few practical universal encoding methods are available. Efficient implementable universal source coding techniques are discussed in this paper. Results are presented on source codes for which a small value of the maximum redundancy is achieved with a relatively short block length. A constructive proof of the existence of universal noiseless codes for discrete stationary sources is first presented. The proof is shown to provide a method for obtaining efficient universal noiseless variable-rate codes for various classes of sources. For memoryless sources, upper and lower bounds are obtained for the minimax redundancy as a function of the block length of the code. Several techniques for constructing universal noiseless source codes for memoryless sources are presented and their redundancies are compared with the bounds. Consideration is given to possible applications to data compression for certain nonstationary sources

The Role of Coding in Multiple-Access Satellite Communication Systems

Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Program / DAAB-07-72-C-025

Spread-Spectrum Random-Access Communications for HF Channels

Coordinated Science Laboratory was formerly known as Control Systems LaboratoryOffice of Naval Research / N00014-80-C-080

Equivalence of two notions of continuity for stationary continuous-time information sources

The notion of continuity for continuous-time information sources which was introduced by Pinsker has found numerous applications in information theory. Continuity in probability is an important concept in the theory of continuous-time stochastic processes. It is shown that these two forms of continuity are equivalent for stationary processes whose state space is a separable metric space.Continuous-time information sources information theory metric space-valued stochastic processes stationary stochastic processes continuity in probability continuity in the sense of Pinsker

Frequency-Hop Transmission for Satellite Packet Switching and Terrestrial Packet Radio Networks

Coordinated Science Laboratory was formerly known as Control Systems LaboratoryOpe