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1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)

4-4 Sept. 1998

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  • IEEE Fifth International Symposium on Spread Spectrum Techniques and Applications [front matter]

    Publication Year: 1998, Page(s):0_2 - 0_12
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    Freely Available from IEEE
  • Long vs short spreading codes in cellular DS-CDMA

    Publication Year: 1998, Page(s):681 - 685 vol.3
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (528 KB)

    The performance of cellular DS-CDMA systems using long and short spreading sequences is compared in terms of bit error probability, and both conventional and MMSE detectors are considered. A slightly higher performance variability is found for the short code case and code hopping as a technique to mitigate this is investigated View full abstract»

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  • A spread CDMA slotted ALOHA system with hybrid ARQ for satellite multiple access

    Publication Year: 1998, Page(s):729 - 733 vol.3
    Cited by:  Papers (1)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (464 KB)

    In the present paper we propose and investigate a new type of satellite multiple access protocol that combines the characteristics of the spread slotted ALOHA (SSA) protocol with the hybrid-ARQ error controlling and retransmission system in order to increase the throughput, in terms of the number of retransmissions, and to keep the BER of the satellite link low when the channel experiences heavy t... View full abstract»

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  • On the Hamming correlation distribution of SFH signature sequence sets

    Publication Year: 1998, Page(s):676 - 680 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (472 KB)

    New results are given on the distribution of periodic Hamming correlation values for well-known slow frequency hopping (SFH) signature sequence sets obtained from cyclically permutable subsets of q-ary Reed-Solomon codes. We also give results on the average of partial Hamming correlation. These kinds of sequence sets have applications in asynchronous SFH packet radio systems View full abstract»

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  • Signal design and in-orbit performance of the new microwave satellite tracking system PRARE

    Publication Year: 1998, Page(s):724 - 728 vol.3
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (416 KB)

    The new two-way microwave satellite tracking system PRARE has been in continuous operation on-board ERS-2 since May 1, 1995. With the assistance of a network of mobile, autonomous PRARE ground stations, the PRARE space segment generates on a global basis two-way pseudonoise-coded range and carrier shifted Doppler measurements at the sub-dm resp. sub-mm/s level of accuracy. These data are primarily... View full abstract»

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  • Highly integrated chips for commercial CDMA-based satcom applications: some case studies

    Publication Year: 1998, Page(s):912 - 916 vol.3
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (708 KB)

    A number of commercial CDMA-based satellite communication applications are discussed. They were realized using highly integrated digital baseband chips. The provision of on-chip hardware for S-CDMA (synchronous CDMA) transmission and demodulation allows for a significant capacity increase. The integration of on-chip microcontrollers reduces power consumption and board size. For small to volumes, A... View full abstract»

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  • A novel transmission diversity system in TDD-CDMA

    Publication Year: 1998, Page(s):771 - 775 vol.3
    Cited by:  Papers (23)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (484 KB)

    This paper presents a novel transmission diversity scheme for code division multiple access system. Conventional diversity receivers in mobile stations require space and complicated circuits, however, the proposed diversity schemes presents significant diversity effect without any diversity equipment at the mobile station. It is possible to use the transmitter diversity at the base station by usin... View full abstract»

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  • Fast adaptive interference cancellation in low cost SAW based chirp spread spectrum systems

    Publication Year: 1998, Page(s):883 - 887 vol.3
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (408 KB)

    For fast reliable data transmission in a heavily distorted indoor environment, a SAW based chirp spread spectrum system operating in the 2.45 GHz ISM is presented. Due to the implementation of SAW matched filters for impulse compression, the system design remains low cost. The use of a bandwidth as wide as allowed make it possible to overcome Rayleigh fading with large coherence bandwidths. A matc... View full abstract»

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  • High capacity synchronous FH/SSMA networks with turbo coding

    Publication Year: 1998, Page(s):973 - 977 vol.3
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (464 KB)

    In this paper, the performance of turbo codes is investigated in a high capacity synchronous FH/SSMA cellular network. A new iterative scheme for updating the branch metrics of the turbo decoder is proposed. The performance of turbo codes is also compared with that of RS codes with parallel decoding. It is argued that, for this network architecture, turbo codes, with soft-input decoding, can achie... View full abstract»

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  • Multiuser detection analysis in DS-CDMA communication systems with Nakagami fading channels

    Publication Year: 1998, Page(s):932 - 935 vol.3
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (336 KB)

    The multiuser detection (MUD) performance analysis in a synchronous direct sequence code division multiple access (DS-CDMA) system using decorrelating and decision feedback (DFB) receivers, including single path Nakagami fading channel is presented. The lower bounds of the receivers bit error probability (BER) are derived. The analytical and numerical results show that the DFB receiver performs be... View full abstract»

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  • CDMA sectorized distributed antenna system

    Publication Year: 1998, Page(s):792 - 797 vol.3
    Cited by:  Papers (14)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (656 KB)

    The objective of this study is to utilize antennas in novel ways so as to achieve performance benefits at the system level in future wireless networks. Despite possessing many appealing features, CDMA distributed antenna (DA) systems suffer from low capacity per antenna element (AE) as a result of the multiple access interference (MAI) accumulated in the common feeder. To overcome this capacity li... View full abstract»

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  • Remarks on designing a CDMA-network

    Publication Year: 1998, Page(s):757 - 761 vol.3
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (360 KB)

    This paper focus on design issues of direct-sequence spread-spectrum networks. The tradeoffs between available bandwidth, necessary data rate, processing gain and the number of selective addressable information channels is investigated. The tradeoffs for synchronous and asynchronous code division multiple access are shown for bandwidth or power limited channels in additive white Gaussian noise. So... View full abstract»

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  • DS-CDMA coherent uplink for mobile satellite communications

    Publication Year: 1998, Page(s):719 - 723 vol.3
    Cited by:  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (488 KB)

    A pilot-aided coherent up-link transmission scheme is proposed for mobile satellite communications at L-band. The scheme is designed to possess small envelope fluctuations and low complexity. A rigorous analysis is performed for the proposed technique, when used in conjunction with a DS-CDMA, convolutionally encoded BPSK link. The analysis is validated through extensive simulations, which in addit... View full abstract»

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  • A frequency error resistant blind interference-mitigating CDMA detector

    Publication Year: 1998, Page(s):858 - 862 vol.3
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (456 KB)

    This paper presents an enhanced version of the previously-proposed blind adaptive interference detector (BAID) for direct-sequence code division multiple access (DS-CDMA) transmission. Such a new detector, named extended complex BAID (EC-BAID), reveals resistance to a possible large frequency shift (e.g., Doppler shift) on interfering carriers, and features invariance to the phase error on the use... View full abstract»

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  • Range sidelobe suppression for pulse compression radars utilizing modified RLS algorithm

    Publication Year: 1998, Page(s):1008 - 1011 vol.3
    Cited by:  Papers (16)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (320 KB)

    This paper analyses the possibility of using the modified recursive method of least squares as a transversal filter coefficients evaluation algorithm which is efficient in self-clutter suppression for phase-coded radar signals. The obtained results are compared with the best results reported in solving this problem, obtained by using iterative reweighted least squares (IRLS) procedure View full abstract»

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  • Chip-level receivers in optical overlapping PPM-CDMA

    Publication Year: 1998, Page(s):907 - 911 vol.3
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (404 KB)

    A chip-level detector for optical overlapping pulse-position modulation code-division multiple-access (OPPM-CDMA) communication systems is proposed. The bit error rate of the proposed system is derived and compared to some traditional receivers under the constraints of fixed data rate and laser pulsewidth. These traditional receivers include OOK-, PPM-, and OPPM-CDMA correlators. The throughput li... View full abstract»

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  • Fundamental BER-floor for long-code CDMA

    Publication Year: 1998, Page(s):692 - 695 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (400 KB)

    In a discrete-time realisation of a long-code CDMA system, a non-zero probability of encountering a singular channel (linear dependency among spreading codes) leads to an inherent error floor at high SNR. In this paper we derive a lower bound on this error floor for a synchronous CDMA system in AWGN. The lower bound is found to correspond closely to the error floor encountered by the full-complexi... View full abstract»

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  • An autonomous distributed inter-vehicle communication network using multicode sense CDMA

    Publication Year: 1998, Page(s):738 - 742 vol.3
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (496 KB)

    This paper describes an autonomous distributed inter-vehicle communication network using multicode sense (MCS) CDMA. Each vehicle in our discussed network broadcasts its cruising information with equal transmission power. When considering an inter-vehicle broadcasting CDMA network, spreading code assignment and notification problems arise. The multicode sense (MCS) CDMA system is proposed as a sim... View full abstract»

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  • Transmit diversity by antenna selection in CDMA downlink

    Publication Year: 1998, Page(s):767 - 770 vol.3
    Cited by:  Papers (27)  |  Patents (31)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (392 KB)

    We study transmit diversity concepts in DS/CDMA wireless networks with multiple transmit antennas. The previously proposed diversity techniques are reviewed and their performance is compared to a selective transmit diversity (STD) concept, proposed here for CDMA systems. In all the competing concepts the encoded bits are distributed to all transmit antennas, whereas in the proposed concept bit are... View full abstract»

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  • Optimum multi-user signal detector in SSMA communication systems based on neural networks

    Publication Year: 1998, Page(s):868 - 872 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (420 KB)

    This paper is motivated by the fact that, in a multi-user CDMA system, the conventional receiver suffers severe performance degradation as the relative powers of the interfering signals becomes large (i.e., “near-far problem”). Furthermore, in many cases the optimum multi-user receiver, which alleviates the near-far problem, is too complex to be of practical use. By viewing this optimu... View full abstract»

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  • Performance of CDMA system using analog PN sequences produced by code-orthogonalizing filter

    Publication Year: 1998, Page(s):701 - 705 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (540 KB)

    This paper proposes a novel asynchronous direct sequence/code division multiple access (DS/CDMA) communication system using analog PN sequences that have an orthogonal relation for all users due to the code-orthogonalizing filter (COF). In the base station receiver, the tap coefficients of the COF can be adaptively controlled “to orthogonalize” or “to approach to orthogonalize&rd... View full abstract»

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  • A modified blind adaptive multiuser CDMA detector

    Publication Year: 1998, Page(s):878 - 882 vol.3
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (552 KB)

    We propose a modified blind adaptive multiuser detector. It is designed to surmount the problems that the blind adaptive detector of Honig, Madhow and Verdu (see IEEE Trans. Inform. Theory, vol.41, no.4, p.944-60, 1995) has in the multipath scenario. It needs to know the spreading code and timings of the significant multipath signals of the desired user, but is actually a “blinder” det... View full abstract»

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  • Nonorthogonal BFSK/FHMA in Rayleigh fading channels

    Publication Year: 1998, Page(s):968 - 972 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (444 KB)

    A nonorthogonal binary FSK (BFSK) is considered in frequency-hopped multiple-access communication systems with Reed-Solomon coding. The effect of tone spacing on the average number of successfully transmitted information bits per unit time, per unit bandwidth normalized throughput, is examined in Rayleigh channels. The tradeoff among tone spacing, code rate, and number of frequency slots in maximi... View full abstract»

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  • A combined coherent carrier recovery and decision-directed delay-lock-loop scheme for DS/SSMA communication systems employing complex spreading sequences

    Publication Year: 1998, Page(s):837 - 842 vol.3
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (568 KB)

    The majority of papers on code synchronization loop design for DSSS communication systems concentrate on noncoherent schemes employing binary spreading sequences with loop structures comprising early and late arm structures with squaring devices which are very prone to arm imbalance effects. In this paper a novel decision-directed code-lock-loop (DD-CLL) synchronization scheme is proposed for DS/S... View full abstract»

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  • Multistage detector for adaptive separation of QAM-modulated multiuser CDMA signals

    Publication Year: 1998, Page(s):927 - 931 vol.3
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (456 KB)

    Code division multiple access (CDMA) proves to be an attractive method for multiuser communication due to its potential capacity increase and anti-multipath fading capability. However, its performance is limited by the existence of multiple access interference energy (MAI), which results in the so called near-far problem. To reduce the MAI effect, different structures for multiuser separators have... View full abstract»

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