Communication channels are said to be underspread if their coherence time is greater than their delay spread. In such cases it can be shown that in the infinite bandwidth limit the information capacity tends to that of a channel with perfect receiver Channel State Information (CSI). This paper presents a lower bound on the capacity of a channel with finite bandwidth, expressed in a form which i...

The strong capacity of a particular channel can be interpreted as a sharp limit on the amount of information which can be transmitted reliably over that channel. To evaluate the strong capacity of a particular channel one must prove both the direct part of the channel coding theorem and the strong converse for the channel. Here we consider the strong converse theorem for the periodic quantum ch...

This paper studies identification of systems in which the system output is quantized, transmitted through a digital communication channel, and observed afterwards. The concept of the CR Ratio is introduced to characterize impact of communication channels on identification. The relationship between the CR Ratio and Shannon channel capacity is discussed. Identification algorithms are further deve...

We highlight some recent results on the theory and algorithms for MIMO systems, obtained at the Royal Institute of Technology (KTH) within the SATURN project. The paper includes a a new approximate expression for the ergodic channel capacity of a MIMO system with correlated fading, algorithms for MIMO beamforming under EIRP (equivalent isotropic radiated power) constraints and a low-complexity ...

This paper studies the impact of a transmitter’s molecule generation process on the capacity of a concentration based Molecular Communication (MC) system. Constraints caused by the molecule generation process affect the availability of the molecules at the transmitter. The transmitter has a storage of molecules, and should decide whether to release or save the currently produced molecules. As a...

For the model of communication through a discrete memoryless channel using i.i.d. random block codes, where the channel is changing slowly from block to block, we propose a stochastic algorithm for adaptation of the generating distribution of the code in the process of continuous reliable communication. The purpose of the algorithm is to match the generating distribution Q(x) to the changing ch...

In this paper, a guideline is provided for design and optimization of the shape of active transport molecular communication channels. In particular rectangular channels are considered and it is shown that for channels employing a single microtubule as the carrier of the information particles, the smaller the perimeter of the channel, the higher the channel capacity. Furthermore, it is shown tha...

i Information capacity of Gaussian channels is one of the basic problems of information theory. Shannon's results for white Gaussian channels and Fano's "waterfilling" analysis of stationary Gaussian channels are two of the best-known works of early information theory. Results are given here which extend to a general framework these results and others due to Gallager and to Kadota, Zakai, and Z...

This paper studies the transceiver design of the Gaussian two-pair two-way relay channel (TWRC), where two pairs of users exchange information through a common relay in a pairwise manner. Our main contribution is to show that the capacity of the Gaussian two-pair TWRC is achievable to within 1 2 bit for arbitrary channel conditions. In the proof, we develop a hybrid coding scheme involving Gaus...

The eigenvalue densities of complex noncentral Wishart matrices are investigated to study an open problem in information theory. Specifically, the largest, smallest and joint eigenvalue densities of complex noncentral Wishart matrices are derived. These densities are expressed in terms of complex zonal polynomials and invariant polynomials. The connection between the complex Wishart matrix theo...