The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we present a novel way for solving the main problem of designing the capacity approaching irregular low-density parity-check (LDPC) code ensemble over binary erasure channel (BEC). The proposed method is much simpler, faster, accurate and practical than other methods. Our method does not use any relaxation or any approximate solution like previous works. Our method works and finds optimal...
In this paper, the Interference Network with General Message Sets (IN-GMS) is introduced in which several transmitters send messages to several receivers: Each subset of transmitters transmit an individual message to each subset of receivers. For such a general scenario, an achievability scheme is presented using the random coding. This scheme is systematically built based on the capacity achieving...
Communication networks conventionally operate with half-duplex methods and interference avoiding schemes to manage multiple transceivers. Here we consider a method in which nodes transmit and receive in concert to achieve full duplex communication without transmitter coordination. We build on a recent framework for full-duplex communication in ad-hoc wireless networks recently proposed by Zhang, Luo...
Compressive sampling is a technique of recovering sparse N-dimensional signals from low-dimensional sketches, i.e., their linear images in Rm, m ≪ N. The main question associated with this technique is construction of linear operators that allow faithful recovery of the signal from its sketch. The most frequently used sufficient condition for robust recovery is the near-isometry property of the operator...
Rank modulation is a way of encoding information to correct errors in flash memory devices as well as impulse noise in transmission lines. Modeling rank modulation involves construction of packings of the space of permutations equipped with the Kendall tau distance. In a recent work we suggested several general constructions of codes in permutations that cover a broad range of code parameters. Here...
Even though in many network scenarios erasure-impaired sources represent a more appropriate data model than frequently used Gaussian and binary sources, they only recently entered the scene of compression coding through introduction of binary erasure quantization over sparse graphs. Binary erasure quantization (BEQ) considers ternary sources (zeros, ones and erasures), and binary reconstructions where...
The problem of finding optimal querying policy, for expected query complexity of symmetric boolean threshold functions was solved in [1] in the context of collocated networks. In this paper, instead of considering the optimal policy to compute the functions, we define the problem of verification of the function value. We use this idea to provide a simpler proof of the optimal querying policy for threshold...
We provide an improved sphere packing bound for positive and symmetric discrete memoryless channels that significantly improves the pre-factor in front of the exponent. Specifically, the presented bound decays only polynomially in N. Further, for the binary symmetric channel, the order of our pre-factor is tight.
This paper presents a new coding scheme and a corresponding achievable rate region for a class of deterministic interference channels with three sender-receiver pairs (3-DIC). The codebook structure uses rate splitting, Marton coding, and superposition coding. The receivers use interference decoding to exploit the structure of the combined interference signal without uniquely decoding any of the interfering...
This paper studies the problem of broadcasting a common message over a relay network as the canonical platform to investigate the utilities and limitations of traditional relay coding schemes. For a few special classes of networks, such as the 3-node relay channel and the 4-node diamond network, the decode-forward coding scheme by Cover and El Gamal, and its generalization to networks by Xie and Kumar,...
In this paper we establish a new inequality tying together the coding rate, the probability of error and the relative entropy between the channel and the auxiliary output distribution. This inequality is then used to show the strong converse, and to prove that the output distribution of a code must be close, in relative entropy, to the capacity achieving output distribution (for DMC and AWGN). One...
A real time coding system with lookahead consists of a memoryless source, a memoryless channel, an encoder, which encodes the source symbols sequentially with knowledge of future source symbols upto a fixed finite lookahead, d, with or without feedback of the past channel output symbols and a decoder, which sequentially constructs the source symbols using the channel output. The objective is to minimize...
The communication scenario under consideration in this paper corresponds to a multiuser channel with side information and consists of a broadcast channel with two legitimate receivers and an eavesdropper. Mainly, the results obtained are as follows. First, an achievable rate region is provided for the (general) case of discrete-input discrete-output channels, generalizing existing results. Second,...
There is no known network with instantaneous channel state information at the transmitters (CSIT) for which (output) feedback enhances the degrees of freedom (or the signaling dimensions) of the network. In this paper, we show that the DoF of wireless networks with delayed CSIT however, can increase with output feedback. This result is shown by obtaining the degrees of freedom (DoF) region for the...
We consider an additive Gaussian channel with additive Gaussian noise feedback. We first derive an upper bound on the n-block capacity (defined by Cover [1]). It is shown that this upper bound can be obtained by solving a convex optimization problem. With stationarity assumptions on Gaussian noise processes, we characterize the limit of the n-block upper bound and prove that this limit is the upper...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.