Determining the capacity of Gaussian relay channels even with one relaying station has been an open problem for several decades. This paper presents a pair of upper and lower bounds whose gap is no more than 0.5 bit per channel use, for the capacity of Gaussian relay channels with one relaying station.

We consider the additive white Gaussian noise channels. We prove that the error probability of decoding tends to one exponentially for rates above the capacity and derive the optimal exponent function. We shall demonstrate that the information spectrum approach is quite useful for investigating this problem. Keywords—Additive white Gaussian noise channels, Strong converse theorem, Information s...

The capacity region of a two-user Gaussian multiaccess channel with intersymbol interference (ISI), where the inputs pass through respective linear systems and are then superimposed before being corrupted by an additive Gaussian noise process, is found. A novel geometrical method is given to obtain the optimal input power spectral densities and the capacity region. This method can be viewed as ...

A coding theorem is proved for the secret sharing communication system (SSCS) with two Gaussian wiretap channels. This communication system is an extension of both the SSCS with two noiseless channels and the Gaussian wiretap channel (GWC). The admissible region of rates and security levels for the SSCS with two GWC’s is described by the capacities and secrecy capacities of two GWC’s.

Recent results have shown that structured codes can be used to construct good channel codes, source codes and physical layer network codes for Gaussian channels. For Gaussian channels with secrecy constraints, however, efforts to date rely on random codes. In this work, we advocate that structured codes are useful for providing secrecy, and show how to compute the secrecy rate when structured c...

This paper focuses on the analysis of average Gaussian error probabilities in certain fading channels, i.e. we are interested in E[Q( √ pγ] where Q(·) is the Gaussian Q-function, p is a positive real number and γ is a nonnegative random variable. We present a unified analysis of the average Gaussian error probability, derive a compact expression in terms of the Lauricella F (n) D function that ...

This paper presents finite-blocklength achievability bounds for the Gaussian multiple access channel (MAC) and random (RAC) under average-error maximal-power constraints. Using codewords uniformly distributed on a sphere maximum likelihood decoder, derived MAC bound each transmitter's rate matches MolavianJazi-Laneman (2015) in its first- second-order terms, improving remaining terms to $\frac1...