In this paper, we study the transport capacity – the transported bit-meters per symbol period per node, and the space time spectrum power efficiency – the transported bit-meters per Hz per second per square meter per watt for large wireless CDMA ad hoc networks. The node density and processing gain tend to infinity with their ratio kept a constant. The limiting networks consist of infinitely de...

In a two node communication environment, the number of key bits (IK) per observation of the reciprocal channel can be computed using the mutual information between the forward and reverse estimated channels. The mutual information can not be computed in closed form, if the probability density function (pdf) of the channel is unknown. This work studies the computation of IK for an arbitrary chan...

It has been conjectured by Høst-Madsen and Nosratinia that complex Gaussian interference channels with constant channel coefficients have only one degree-of-freedom regardless of the number of users. While several examples are known of constant channels that achieve more than 1 degree of freedom, these special cases only span a subset of measure zero. In other words, for almost all channel coef...

In this study, the problem of transmitting an independent and identically distributed (i.i.d.) Gaussian source over an i.i.d. Gaussian wire-tap channel, with an i.i.d. Gaussian known interference available at the transmitter is considered. The intended receiver is assumed to have a certain minimum signal-to-noise ratio (SNR) and the eavesdropper is assumed to have a strictly lower SNR compared ...

In this paper, we consider a Gaussian multiple access channel with multiple independent additive white Gaussian interferences. Each interference is known to exactly one transmitter non-causally. The capacity region is characterized to within a constant gap regardless of channel parameters. These results are based on a layered modulo-lattice scheme which realizes distributed interference cancell...

In this paper we propose a generalization of the usual deBruijn identity that links the Shannon differential entropy (or the Kullback–Leibler divergence) and the Fisher information (or the Fisher divergence) of the output of a Gaussian channel. The generalization makes use of φ -entropies on the one hand, and of φ -divergences (of the Csizàr class) on the other hand, as generalizations of the S...

The capacity region of a channel consists of all achievable rate vectors. Picking a particular point in the capacity region is synonymous with rate allocation. The issue of fairness in rate allocation is addressed in this paper. We review several notions of fairness, including max-min fairness, proportional fairness and Nash bargaining solution. Their efficiencies for general multiuser channels...

Analog (uncoded) transmission provides a simple and robust scheme for communicating a Gaussian source over a Gaussian channel under the mean squared error (MSE) distortion measure. Unfortunately, its performance is usually inferior to the all-digital, separation-based source-channel coding solution, which requires exact knowledge of the channel at the encoder. The loss comes from the fact that ...

We establish natural connections between continuous-time Gaussian feedback/memory channels and their associated discrete-time versions in the forms of sampling and approximating theorems. It turns out that these connections, together with relevant tools from stochastic calculus, can enhance our understanding of continuous-time Gaussian channels in terms of giving alternative interpretations to ...

Most of the research performed in the area of turbo codes has considered only Additive White Gaussian Noise (AWGN) channels. While some work has extended the coverage of channel noise to fading channels, thus far little research has been performed with heavy-tailed noise distributions. This paper analyzes the performance of the turbo decoder for a class of heavy-tailed noise distributions consi...