10,844 research outputs found

    Protecting U.S. Intellectual Property Rights and the Challenges of Digital Piracy

    Get PDF
    According to U.S. industry and government officials, intellectual property rights (IPR) infringement has reached critical levels in the United States as well as abroad. The speed and ease with which the duplication of products protected by IPR can occur has created an urgent need for industries and governments alike to address the protection of IPR in order to keep markets open to trade in the affected goods. Copyrighted products such as software, movies, music and video recordings, and other media products have been particularly affected by inadequate IPR protection. New tools, such as writable compact discs (CDs) and, of course, the Internet have made duplication not only effortless and low-cost, but anonymous as well. This paper discusses the merits of IPR protection and its importance to the U.S. economy. It then provides background on various technical, legal, and trade policy methods that have been employed to control the infringement of IPR domestically and internationally. This is followed by an analysis of current and future challenges facing U.S. industry with regard to IPR protection, particularly the challenges presented by the Internet and digital piracy.Research and Development/Tech Change/Emerging Technologies,

    Capacity Theorems for the AWGN Multi-Way Relay Channel

    Full text link
    The L-user additive white Gaussian noise multi-way relay channel is considered, where multiple users exchange information through a single relay at a common rate. Existing coding strategies, i.e., complete-decode-forward and compress-forward are shown to be bounded away from the cut-set upper bound at high signal-to-noise ratios (SNR). It is known that the gap between the compress-forward rate and the capacity upper bound is a constant at high SNR, and that between the complete-decode-forward rate and the upper bound increases with SNR at high SNR. In this paper, a functional-decode-forward coding strategy is proposed. It is shown that for L >= 3, complete-decode-forward achieves the capacity when SNR <= 0 dB, and functional-decode-forward achieves the capacity when SNR >= 0 dB. For L=$, functional-decode-forward achieves the capacity asymptotically as SNR increases.Comment: accepted and to be presented at ISIT 201

    Functional-Decode-Forward for the General Discrete Memoryless Two-Way Relay Channel

    Full text link
    We consider the general discrete memoryless two-way relay channel, where two users exchange messages via a relay, and propose two functional-decode-forward coding strategies for this channel. Functional-decode-forward involves the relay decoding a function of the users' messages rather than the individual messages themselves. This function is then broadcast back to the users, which can be used in conjunction with the user's own message to decode the other user's message. Via a numerical example, we show that functional-decode-forward with linear codes is capable of achieving strictly larger sum rates than those achievable by other strategies

    The Binary-Symmetric Parallel-Relay Network

    Full text link
    We present capacity results of the binary-symmetric parallel-relay network, where there is one source, one destination, and K relays in parallel. We show that forwarding relays, where the relays merely transmit their received signals, achieve the capacity in two ways: with coded transmission at the source and a finite number of relays, or uncoded transmission at the source and a sufficiently large number of relays. On the other hand, decoding relays, where the relays decode the source message, re-encode, and forward it to the destination, achieve the capacity when the number of relays is small.Comment: accepted and to be presented at ISIT 201

    Optimal Coding Functions for Pairwise Message Sharing on Finite-Field Multi-Way Relay Channels

    Full text link
    This paper considers the finite-field multi-way relay channel with pairwise message sharing, where multiple users exchange messages through a single relay and where the users may share parts of their source messages (meaning that some message parts are known/common to more than one user). In this paper, we design an optimal functional-decode-forward coding scheme that takes the shared messages into account. More specifically, we design an optimal function for the relay to decode (from the users on the uplink) and forward (back to the users on the downlink). We then show that this proposed function-decode-forward coding scheme can achieve the capacity region of the finite-field multi-way relay channel with pairwise message sharing. This paper generalizes our previous result for the case of three users to any number of users.Comment: Author's final version (accepted for presentation at the 2014 IEEE International Conference on Communications [ICC 2014]

    On Achievable Rate Regions of the Asymmetric AWGN Two-Way Relay Channel

    Full text link
    This paper investigates the additive white Gaussian noise two-way relay channel, where two users exchange messages through a relay. Asymmetrical channels are considered where the users can transmit data at different rates and at different power levels. We modify and improve existing coding schemes to obtain three new achievable rate regions. Comparing four downlink-optimal coding schemes, we show that the scheme that gives the best sum-rate performance is (i) complete-decode-forward, when both users transmit at low signal-to-noise ratio (SNR); (ii) functional-decode-forward with nested lattice codes, when both users transmit at high SNR; (iii) functional-decode-forward with rate splitting and time-division multiplexing, when one user transmits at low SNR and another user at medium--high SNR.Comment: to be presented at ISIT 201
    • …
    corecore