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IEE Proceedings - Communications

Issue 3 • Date 2 June 2006

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Displaying Results 1 - 20 of 20
  • Gallager first bounding technique for the performance evaluation of maximum-likelihood decoded linear binary block codes

    Publication Year: 2006, Page(s):317 - 332
    Cited by:  Papers (5)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (449 KB)

    Exact bit or frame error rate expressions for most communication systems are either too complex or unlikely to exist in nice closed forms. A good alternative is to bound the performance measure by tight enough lower and upper bounds. Many tight upper bounds on the error probability of binary codes are based on the so-called Gallager's first bounding technique (GFBT). In this method, Gallager split... View full abstract»

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  • Direct mapping architecture for JPEG Huffman decoder

    Publication Year: 2006, Page(s):333 - 340
    Cited by:  Papers (3)  |  Patents (4)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (180 KB)

    A novel decoding algorithm for the JPEG Huffman code is presented, in which the alternating current (AC) Huffman table is partitioned into four modules. According to this partition, a direct mapping technique is developed to decode Huffman codewords without any searching or matching operations. Therefore, an algorithm based on this technique can save several controlling circuits and will be simple... View full abstract»

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  • Turbo equalisation of time varying multipath channel under class-A impulsive noise

    Publication Year: 2006, Page(s):341 - 348
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (247 KB)

    The paper explores the problem of turbo equalisation and channel estimation under class-A impulsive noise. The channel is a frequency selective fading channel in which its time varying coefficients are expanded into a finite number of basis sequences and time invariant (TI) expansion parameters. Instead of the application of a maximum likelihood (ML) approach in its standard form, the proposed cha... View full abstract»

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  • Efficient moments-based method for error rate calculations using the Beaulieu series

    Publication Year: 2006, Page(s):349 - 354
    Cited by:  Papers (7)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (167 KB)

    A moments-based method is used for calculating the error probability of partially coherent phase shift keying (PSK) wireless diversity systems. The probability of error is formulated in terms of the Beaulieu series for the cumulative distribution function (cdf) of a sum of random variables. Since the characteristic function (CF) needed in the series derivation might not be known explicitly in some... View full abstract»

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  • Stable and unstable operating regions of slotted ALOHA with number of retransmission attempts and number of power levels

    Publication Year: 2006, Page(s):355 - 364
    Cited by:  Papers (11)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (312 KB)

    A transmission policy for slotted ALOHA is studied in terms of new packet generation rate, number of retransmission attempts and number of power levels. The retransmission cut-off is not required for stable operation of slotted ALOHA if the new packet generation rate is less than a critical limit. Results show that the magnitude of this critical limit of the new packet generation rate is 0.36 for ... View full abstract»

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  • Modelling soft-state protocols with SDL

    Publication Year: 2006, Page(s):365 - 375
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (219 KB)

    The notion of soft state has been introduced in packet-switched networks to achieve particular services for end-to-end communications, such as quality-of-service provisioning and configuration of stateful packet filters. Protocols built upon soft state principles were believed to be simple, however in practice they are far more complex. An important issue with such protocols is to ensure their ope... View full abstract»

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  • Performance evaluation of the loss-collected retransmission scheme in reliable multicast protocol

    Publication Year: 2006, Page(s):376 - 382
    Cited by:  Papers (1)  |  Patents (8)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (225 KB)

    This authors present an enhanced retransmission loss-recovery algorithm based on the XOR selective repeated protocol for reliable multicast delivery. The operation of XOR minimises the number of packets requiring retransmission, reduces network burden, and increases throughput. Furthermore, the analysis presented here provides a basis for selecting a suitable loss-packet size for retransmission to... View full abstract»

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  • Spectra of multimode coded signals

    Publication Year: 2006, Page(s):383 - 391
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (480 KB)

    Multimode coding is an efficient block coding technique that introduces control over sequence statistics by generating a number of alternatives to represent the source word in each encoding interval and then selecting the word that best meets the system constraints. The power spectral density (PSD) of the encoded signal is of particular interest with these codes. Standard techniques for evaluation... View full abstract»

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  • Pilot-aided OFDM/SDMA channel estimation with unknown timing offset

    Publication Year: 2006, Page(s):392 - 398
    Cited by:  Papers (7)  |  Patents (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (340 KB)

    The paper presents a novel approach to estimating the multi-path channel of orthogonal frequency-division multiplexing (OFDM)/spatial-diversity multiple-access (SDMA) systems. Having OFDM/SDMA symbols transmitted not aligned with base station (BS) timing, demodulated signals may severely suffer from an inter-OFDM-symbol interference (ISI), namely the misalignment interference. Consequently, the in... View full abstract»

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  • Performance of network coding based multicast

    Publication Year: 2006, Page(s):399 - 404
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (203 KB)

    In data networks, the selection of routes is an important issue. Regretably, little work about routing algorithms has been reported in the present literature on network coding. In the paper, detailed routing algorithms for network coding based multicast are proposed for low-rate multicast and for high-rate multicast. By using commonly used topology models of the Internet and ad hoc networks, topol... View full abstract»

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  • Modelling CSMA/CA protocol for wireless channels that use collaborative codes modulation

    Publication Year: 2006, Page(s):405 - 409
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (173 KB)

    A new wireless medium access control scheme is proposed for implementing collaborative codes on the carrier sense multiple access with collision avoidance (CSMA/CA) protocol. To simplify the analysis, a new backoff algorithm is suggested that is simple to implement and to model. Markov chain analysis is used for modelling the proposed CC-CSMA/CA protocol. The resulting model describes the regular ... View full abstract»

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  • Semi-blind space-time receiver for multiuser detection of DS/CDMA signals in multipath channels

    Publication Year: 2006, Page(s):410 - 418
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (230 KB)

    We consider the design of a new space-time receiver that is useful in heavily loaded DS/CDMA systems when only small data records are used in detection. This property is desirable for detection of users of high mobility in crowded systems. The receiver is based on the integration of ESPRIT-based space-time beamforming with multiuser detection based on the constant modulus (CM) property. The beamfo... View full abstract»

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  • SINR for DS-CDMA with random spreading

    Publication Year: 2006, Page(s):419 - 424
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (204 KB)

    For wireless multipath fading channels, the performance of a direct-sequence code-division multiple-access (DS-CDMA) system is degraded by the interferences, including the multipath interference (MPI) and the multiuser interference (MUI). For the downlink DS-CDMA with random spreading, we derive the variances of the interferences and obtain the signal-to-interference-plus-noise ratio (SINR). The s... View full abstract»

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  • Performance comparison of packet transmission over IPv6 network on different platforms

    Publication Year: 2006, Page(s):425 - 433
    Cited by:  Papers (3)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (204 KB)

    With the increasing popularity in recent years, many popular operating system (OS) vendors worldwide have incorporated Internet Protocol version 6 (IPv6) into their OS. The performance of the IP stack, together with the behaviour of the OS greatly affects the efficiency of network applications built on top of it. Like any other protocols, the acceptance of various IPv6 implementations heavily reli... View full abstract»

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  • Analytic approach for deploying desktop videoconferencing

    Publication Year: 2006, Page(s):434 - 444
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1047 KB)

    The deployment of desktop videoconferencing, also known as video and voice over IP (VVoIP), over existing IP networks is gaining popularity. Such a deployment has become a major and challenging task for data network researchers and designers. An analytic approach for deploying videoconferencing is presented. The approach utilises queueing network analysis and investigates two key performance bound... View full abstract»

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  • Time-synchronised multi-piconet Bluetooth environments

    Publication Year: 2006, Page(s):445 - 452
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (231 KB)

    Multiple Bluetooth piconets operating in the globally available 2.4 GHz industrial, scientific and medical (ISM) band are likely to co-exist in a physical environment, supporting applications such as wireless earphones, keyboards etc. An independently operating Bluetooth piconet will inevitably encounter the interference from collocated piconets, which results in both individual piconet and overal... View full abstract»

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  • Low-complexity block coded multi-carrier modulation for line-of-sight microwave systems

    Publication Year: 2006, Page(s):453 - 458
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (228 KB)

    The authors present low-complexity block coded multi-carrier modulation (BC-MCM) schemes that more are efficient to overcome the deep frequency-selective fading that appears on high-data-rate transmission line-of-sight digital radio channels. These BC-MCM schemes are based on time-limited orthogonal multi-carrier modulation with waveform shaping (ITLO-MCM) systems associated to an interleaving pro... View full abstract»

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  • Near-optimum transmit power allocation for space-time block encoded wireless communication systems

    Publication Year: 2006, Page(s):459 - 463
    Cited by:  Papers (3)  |  Patents (4)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (294 KB)

    Space-time block codes (STBCs) allow the diversity provided by multiple-input-multiple-output (MIMO) communication channels to be utilised, thereby increasing the capacity over ergodic fading channels or decreasing the outage probability over non-ergodic fading channels. The authors consider the deployment of orthogonal STBCs in spatially distributed mesh networks where the potentially different a... View full abstract»

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  • Efficient bandwidth allocation algorithm for ethernet passive optical networks

    Publication Year: 2006, Page(s):464 - 468
    Cited by:  Papers (21)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (286 KB)

    Bandwidth allocation is one of the critical issues in Ethernet passive optical networks (EPONs). To achieve good network performance and thus provide guaranteed network service to end users, an EPON system must employ an efficient bandwidth allocation algorithm to dynamically allocate the limited bandwidth of the upstream transmission channel among multiple optical network units (ONUs). In the pap... View full abstract»

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  • Load balancing - node transfer trade-off in reconfigurable WDM networks

    Publication Year: 2006, Page(s):469 - 474
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (203 KB)

    When the traffic demand changes in single-hop WDM broadcast and select networks, the load can become unbalanced. This situation leads to poor resource utilisation and the wavelength assignment (WLA) requires reconfiguring to maintain a balanced load. The problem of reconfiguring the wavelength assignment in single-hop WDM networks is considered here. Topologies used in the study are passive star a... View full abstract»

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