In quantum information theory, a basic question often presented is how efficiently can one transmit classical information over a quantum channel.[1, 2, 3] Because of the non-orthogonality of quantum states, the channel capacity is different from that of the classical channel discussed in [4, 5] . Recently, this question has attracted new attention due to the rapid progress in quantum informatio...

We show the equivalence of two different notions of quantum channel capacity: that which uses the entanglement fidelity as its criterion for success in transmission, and that which uses the minimum fidelity of pure states in a subspace of the input Hilbert space as its criterion. As a corollary, any source with entropy less than the capacity may be transmitted with high entanglement fidelity. W...

Prior entanglement between sender and receiver, which exactly doubles the classical capacity of a noiseless quantum channel, can increase the classical capacity of some noisy quantum channels by an arbitrarily large constant factor depending on the channel, relative to the best known classical capacity achievable without entanglement. The enhancement factor is greatest for very noisy channels, ...

A strong converse theorem for channel capacity establishes that the error probability in any communication scheme for a given channel necessarily tends to one if the rate of communication exceeds the channel’s capacity. Establishing such a theorem for the quantum capacity of degradable channels has been an elusive task, with the strongest progress so far being a so-called “pretty strong convers...

co-channel interference is a major factor in limiting the capacity and link quality in cellular communications. as the co-channel interference is modeled by lognormal distribution, sum of the co-channel interferences of neighboring cells is represented by the sum of lognormal random variables (rvs) which has no closed-form expression. assuming independent, identically distributed (iid) rvs, the...

In the past decade a considerable amount of research has been done on schema integration and translation. Until recently, most of the work has largely neglected the proof of correctness in transforming schemas. Anomalies could arise due to errors in the transformation rules. Invalid transformations can produce incomplete or inconsistent pictures that may cause damage to organisations. In this p...

Measurements taken at the campus of Brigham Young University (BYU) are used to investigate the statistical properties of the indoor MIMO channel. Two statistical tests, Royston’s and HenzeZirkler’s, are applied to the MIMO data to assess whether the data belongs to a multivariate normal distribution or not. The possibility of modeling the covariance matrix as a Kronecker product of the correlat...

With the rapid development of high-speed railways, demands on high mobility wireless communication increase greatly. To provide stable and high data rate wireless access for users in the train, it is necessary to properly deploy base stations along the railway. In this paper, we consider this issue from the perspective of channel service which is defined as the integral of the timevarying insta...

The restriction to Gaussian inputs in the limiting expression for the capacity regions of memoryless Gaussian interference and multiple-access channels is shown to fall short of achieving capacity even if the inputs are allowed to be dependent and nonstationary. In addition, the equality between the limiting and the single-letter characterizations of memoryless multiple-access channel capacity ...