This paper extends recent results on steganographic capacity. We derive capacity expressions for perfectly-secure steganographic systems. The warden may be passive, or active using a memoryless attack channel, or active using an arbitrarily varying channel. Neither encoder nor decoder know which channel was selected by the warden. In some cases, the steganographic constraint does not result in ...

The Gaussian vector multiple access channel with a sum-power constraint across all users, rather than the usual individual power constraint on each user, has recently been shown to be the dual of a Gaussian vector broadcast channel [1] [2]. Further, a numerical algorithm for the sum capacity under the sum power constraint has been proposed in [3]. This paper proposes a different algorithm for t...

In the present note we discuss in details the Riemann problem for a one-dimensional hyperbolic conservation law subject to a point constraint. We investigate how the regularity of the constraint operator impacts the well--posedness of the problem, namely in the case, relevant for numerical applications, of a discretized exit capacity. We devote particular attention to the case in which the cons...

Communication over a discrete time-varying Rician fading channel is considered, where neither the transmitter nor the receiver has the knowledge of the channel state information (CSI) except the fading statistics. We provide closed form expressions to the mutual information under both average and peak input power constraint when its distribution is complex Gaussian. The results are compared wit...

‎in this paper, using the idea of convexificators, we study boundedness and nonemptiness of lagrange multipliers satisfying the first order necessary conditions. we consider a class of nons- mooth fractional programming problems with equality, inequality constraints and an arbitrary set constraint. within this context, define generalized mangasarian-fromovitz constraint qualification and show t...

In this work, we study two models of arbitrarily varying channels, when causal side information is available at the encoder in a causal manner. First, we study the arbitrarily varying channel (AVC) with input and state constraints, when the encoder has state information in a causal manner. Lower and upper bounds on the random code capacity are developed. A lower bound on the deterministic code ...

Corpus studies by Schuler, AbdelRahman, Miller, and Schwartz (2010), appear to support a model of comprehension taking place in a general-purpose working memory store, by providing an existence proof that a simple probabilistic sequence model over stores of up to four syntacticallycontiguous memory elements has the capacity to reconstruct phrase structure trees for over 99.9% of the sentences i...

It has been recently advocated that in large communication systems it is beneficial both for the users and for the network as a whole to store content closer to users. One particular implementation of such an approach is to co-locate caches with wireless base stations. In this paper we study geographically distributed caching of a fixed collection of files. We model cache placement with the hel...

Corpus studies by Schuler, AbdelRahman, Miller, and Schwartz (2010), appear to support a model of comprehension taking place in a general-purpose working memory store, by providing an existence proof that a simple probabilistic sequence model over stores of up to four syntacticallycontiguous memory elements has the capacity to reconstruct phrase structure trees for over 99.9% of the sentences i...

This paper considers the design of signature waveforms that optimize the total capacity of multiuser decoders for the QAM-synchronous Gaussian multiple-access channel under a Fractional Out-of-Band Power (FOBP) bandwidth constraint. In doing so, it imposes a hitherto unrecognized constraint that is relevant in wireless communication networks: the bandwidth must be independent of the location at...