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Journal of Communications and Networks

Issue 5 • Date Oct. 2012

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Displaying Results 1 - 21 of 21
  • Improved parameter estimation with threshold adaptation of cognitive local sensors

    Publication Year: 2012, Page(s):471 - 480
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2252 KB) | HTML iconHTML

    Reliable detection of primary user activity increases the opportunity to access temporarily unused bands and prevents harmful interference to the primary system. By extracting a global decision from local sensing results, cooperative sensing achieves high reliability against multipath fading. For the effective combining of sensing results, which is generalized by a likelihood ratio test, the fusio... View full abstract»

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  • Estimation of the number of sources based on hypothesis testing

    Publication Year: 2012, Page(s):481 - 486
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1467 KB) | HTML iconHTML

    Accurate and efficient estimation of the number of sources is critical for providing the parameter of targets in problems of array signal processing and blind source separation among other such problems. When conventional estimators work in unfavorable scenarios, e.g., at low signal-to-noise ratio (SNR), with a small number of snapshots, or for sources with a different strength, it is challenging ... View full abstract»

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  • Interference priority: A new scheme for prioritized resource allocation in wireless

    Publication Year: 2012, Page(s):487 - 494
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2043 KB) | HTML iconHTML

    A standard paradigm for the allocation of wireless resources in communication demands symmetry, that is, all users are assumed to be on equal footing and hence get equal shares of the system's communication capabilities. However, there are situations in which “prime users” should be given priority, as for example in the transmission of emergency messages. We examine prioritization po... View full abstract»

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  • Prioritized resource allocation in wireless spectrum pooling

    Publication Year: 2012, Page(s):495 - 500
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (842 KB) | HTML iconHTML

    A standard paradigm for the allocation of wireless resources in communication demands symmetry, whereby all users are assumed to be on equal footing and hence get equal shares of communication capabilities. However, there are situations in which “prime users” should be given higher priority, as for example in the transmission of emergency messages. In this paper, we examine a priorit... View full abstract»

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  • A joint timing synchronization, channel estimation, and SFD detection for IR-UWB systems

    Publication Year: 2012, Page(s):501 - 509
    Cited by:  Papers (1)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (3404 KB) | HTML iconHTML

    This paper proposes a joint timing synchronization, channel estimation, and data detection for the impulse radio ultrawideband systems. The proposed timing synchronizer consists of coarse and fine timing estimation. The synchronizer discovers synchronization points in two stages and performs adaptive threshold based on the maximum pulse averaging and maximum (MAX-PA) method for more precise synchr... View full abstract»

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  • Performance analysis of VoIP services in mobile WiMAX systems with a hybrid ARQ scheme

    Publication Year: 2012, Page(s):510 - 517
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2433 KB) | HTML iconHTML

    This paper analyzes the performance of voice-over-Internet protocol (VoIP) services in terms of the system throughput, the packet delay, and the signaling overhead in a mobile WiMAX system with a hybrid automatic repeat request (HARQ) mechanism. Furthermore, a queueing analytical model is developed with due consideration of adaptive modulation and coding, the signaling overhead, and the retransmis... View full abstract»

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  • Performance comparison of coherent and non-coherent detection schemes in LR-UWB system

    Publication Year: 2012, Page(s):518 - 523
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (3398 KB) | HTML iconHTML

    This paper presents new coherent and non-coherent detection methods for the IEEE 802.15.4a low-rate ultra-wideband physical layer with forward error correction (FEC) coding techniques. The coherent detection method involving channel estimation is based on the correlation characteristics of the preamble signal. A coherent receiver uses novel iterated selective-rake (IT-SRAKE) to detect 2-bit data i... View full abstract»

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  • Throughput and delay analysis of a reliable cooperative MAC protocol in ad hoc networks

    Publication Year: 2012, Page(s):524 - 532
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (4024 KB) | HTML iconHTML

    In this paper, we present the performance evaluation of the reliable cooperative media access control (RCO-MAC) protocol, which has been proposed in [1] by us in order to enhance system throughput in bad wireless channel environments. The performance of this protocol is evaluated with computer simulation as well as mathematical analysis in thispaper. The system throughput, two types of average del... View full abstract»

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  • Analysis of TDOA and TDOA/SS based geolocation techniques in a non-line-of-sight environment

    Publication Year: 2012, Page(s):533 - 539
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (834 KB) | HTML iconHTML

    The performance analysis of wireless geolocation in a non-line-of-sight (NLOS) environment is a very important issue. Since Cramer-Rao lower bound (CRLB) determines the physical impossibility of the variance of an unbiased estimator being less than the bound, many studies presented the performance analysis in terms of CRLB. Several CRLBs for time-of-arrival (TOA), pseudo-range TOA, angle-of-arriva... View full abstract»

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  • Lagged cross-correlation of probability density functions and application to blind equalization

    Publication Year: 2012, Page(s):540 - 545
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1101 KB) | HTML iconHTML

    In this paper, the lagged cross-correlation of two probability density functions constructed by kernel density estimation is proposed, and by maximizing the proposed function, adaptive filtering algorithms for supervised and unsupervised training are also introduced. From the results of simulation for blind equalization applications in multipath channels with impulsive and slowly varying direct cu... View full abstract»

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  • Space-stretch tradeoff optimization for routing in Internet-like graphs

    Publication Year: 2012, Page(s):546 - 553
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1079 KB) | HTML iconHTML

    Compact routing intends to achieve good tradeoff between the routing path length and the memory overhead, and is recently considered as a main alternative to overcome the fundamental scaling problems of the Internet routing system. Plenty of studies have been conducted on compact routing, and quite a few universal compact routing schemes have been designed for arbitrary network topologies. However... View full abstract»

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  • Cross-layer and end-to-end optimization for the integrated wireless and wireline network

    Publication Year: 2012, Page(s):554 - 565
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2396 KB) | HTML iconHTML

    In this paper, we study a cross-layer and end-to-end optimization problem for the integrated wireless and wireline network that consists of one wireline core network and multiple wireless access networks. We consider joint end-to-end flow control/distribution at the transport and network layers and opportunistic scheduling at the data link and physical layers. We formulate a single stochastic opti... View full abstract»

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  • Neighbor discovery in a wireless sensor network: Multipacket reception capability and physical-layer signal processing

    Publication Year: 2012, Page(s):566 - 577
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1708 KB) | HTML iconHTML

    In randomly deployed networks, such as sensor networks, an important problem for each node is to discover its neighbor nodes so that the connectivity amongst nodes can be established. In this paper, we consider this problem by incorporating the physical layer parameters in contrast to the most of the previous work which assumed a collision channel. Specifically, the pilot signals that nodes transm... View full abstract»

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  • Multi-objective handover in LTE macro/femto-cell networks

    Publication Year: 2012, Page(s):578 - 587
    Cited by:  Papers (12)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (4631 KB) | HTML iconHTML

    One of the key elements in the emerging, packet-based long term evolution (LTE) cellular systems is the deployment of multiple femtocells for the improvement of coverage and data rate. However, arbitrary overlaps in the coverage of these femto-cells make the handover operation more complex and challenging. As the existing handover strategy of LTE systems considers only carrier to interference plus... View full abstract»

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    Publication Year: 2012, Page(s): 1
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  • Journal of Communications and Networks - Call for papers

    Publication Year: 2012, Page(s): 1
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  • Journal of Communications and Networks - Call for papers

    Publication Year: 2012, Page(s): 1
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  • Table of Contents [Front cover]

    Publication Year: 2012, Page(s): c1
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  • Table of Contents [Back cover]

    Publication Year: 2012, Page(s): c4
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  • [Front inside cover]

    Publication Year: 2012, Page(s): c2
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  • [Back inside cover]

    Publication Year: 2012, Page(s): c3
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Aims & Scope

The Journal of Communications and Networks is published six times per year, and is committed to publishing high-quality papers that advance the state-of-the-art and practical applications of communications and information networks.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Anthony Ephremides
University of Maryland