Let X → Y → Z be a discrete memoryless degraded broadcast channel (DBC) with marginal transition probability matrices TY X and TZX . Denote q as the distribution of the channel input X . For any given q, and H(Y |X) ≤ s ≤ H(Y ), where H(Y |X) is the conditional entropy of Y given X and H(Y ) is the entropy of Y , define the function F ∗ TY X ,TZX (q, s) as the infimum of H(Z|U), the conditional...

construction of the intake structures to divert some portion of flow water from a main channel causes some variations of flow conditions at the intake entrance. these variations cause the reinforcement of the eddy flow and sedimentation in the bank of the intake. an effective measure to control the entry sediment is the use of submerged vanes. most of previous studies in this regards have been ...

We address the problem of universal communications over an unknown channel with an instantaneous noiseless feedback, and show how rates corresponding to the empirical behavior of the channel can be attained, although no rate can be guaranteed in advance. First, we consider a discrete moduloadditive channel with alphabet X , where the noise sequence Z is arbitrary and unknown and may causally de...

The upper bound on the capacity of a 3-node discrete memoryless relay channel is considered, where a sourceX wants to send information to destination Y with the help of a relay Z. Y and Z are independent given X , andthe link from Z to Y is lossless with rate R0. A new inequality is introduced to upper-bound the capacity whenthe encoding rate is beyond the capacities of both individ...

We give some inequalities of capacity in Gaussian channel with or without feedback. The nonfeedback capacity Cn,Z(P ) and the feedback capacity Cn,FB,Z(P ) are both concave functions of P . Though it is shown that Cn,Z(P ) is a convex function of Z in some sense, Cn,FB,Z(P ) is a convex like function of Z.

Consider a memoryless degraded broadcast channel (DBC) in which the channel output is a singleletter function of the channel input and the channel noise. As examples, for the Gaussian broadcast channel (BC) this single-letter function is regular Euclidian addition and for the binary-symmetric BC this single-letter function is Galois-Field-two addition. This paper identifies several classes of d...

The first terms of the low-signal-energy asymptotics for the mutual information in the discrete-time Poisson channel are derived and compared to an asymptotic expression of the capacity. In the presence of non-zero additive noise (either Poisson or geometric), the mutual information is concave at zero signal-energy and the minimum energy per bit is not attained at zero capacity. Fixed signal co...

An Adaptive tranSmission mechanism exploiting both interference loCality and the relationship between dEsired sigNal and inTerference (ASCENT) is proposed for uplink transmission in heterogeneous networks. The authors adopt both X channel and Z channel models according to which spatial signal processing is designed. In the X channel, the picocell base station (PBS) exploits information the macr...