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Global Telecommunications Conference, 1991. GLOBECOM '91. 'Countdown to the New Millennium. Featuring a Mini-Theme on: Personal Communications Services

2-5 Dec. 1991

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  • IEEE Global Telecommunications Conference. GLOBECOM '91. Countdown to the New Millennium. Featuring a Mini-Theme on: Personal Communications Services (PCS). Conference Record (Cat. No.91CH2980-1)

    Publication Year: 1991
    Request permission for commercial reuse | PDF file iconPDF (66 KB)
    Freely Available from IEEE
  • Jitter and bandwidth enforcement

    Publication Year: 1991, Page(s):261 - 265 vol.1
    Cited by:  Papers (18)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (357 KB)

    Cells arriving at an ATM (asynchronous transfer mode) network experience random delays due to queuing in upstream multiplexing stages. The alteration of the initial periodic nature of a constant bit rate cell stream due to such delays is the phenomenon of jitter. An assumption of Markovian dependence between the delays of successive cells makes it possible to calculate various quantities of intere... View full abstract»

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  • Transmission of SDH signals through future satellite channels using 16-ary QAM technique

    Publication Year: 1991, Page(s):510 - 514 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (276 KB)

    The authors discuss the possibility of transmitting synchronous digital hierarchy (SDH) signals through two-link nonlinear satellite channels. Transmitting such high-bit-rate signals through standard 54-MHz transponder bandwidth requires the use of high-level modulation schemes. The techniques and technologies needed to make the use of 16-ary QAM (quadrature amplitude modulation) transmission feas... View full abstract»

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  • Optical communications in RACE

    Publication Year: 1991, Page(s):1515 - 1516 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (76 KB)

    Summary form only given. The European Community is undertaking a major effort in research and development of advanced communications technologies including fiber-optic communication for integrated broadband networks. In recognition of the vital importance of effective communication services to Europe's economic and social development, the European Economic Community has launched a joint effort, th... View full abstract»

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  • A new solution technique for discrete queueing analysis of ATM system

    Publication Year: 1991, Page(s):358 - 364 vol.1
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (520 KB)

    The authors present a general solution technique for the discrete-time queuing analysis of ATM (asynchronous transfer mode) systems. The traffic is characterized as an r-dependent Markov modulated phase-type process, and the queue is assumed to have finite capacity and multiple servers with fixed service time. The queue is functionally modeled as a nonlinear feedback loop and a procedure ... View full abstract»

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  • An approach to characterizing response time based on queue-length probabilities in queueing systems

    Publication Year: 1991, Page(s):352 - 357 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (392 KB)

    A technique is proposed for characterizing the response (or waiting) times in terms of probability distribution function or percentiles (e.g. 95th percentiles), given the set of queue-length probabilities. This approach makes use of the Laguerre functions to approximate the distribution functions. A numerical study has been conducted to validate the approach. The high accuracy of the numerical res... View full abstract»

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  • Approaches to detecting and resolving feature interactions

    Publication Year: 1991, Page(s):1371 - 1377 vol.2
    Cited by:  Papers (2)  |  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (516 KB)

    A framework is suggested for specifying call processing features independently and discovering conflicts when their specifications are merged. Features are defined on a common call model that partitions in the state space into separable concerns. Each feature proposes state transition rules that define explicitly how the partitions would be interrelated by causes, effects, and conditions. Generic ... View full abstract»

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  • DC free runlength-limited codes

    Publication Year: 1991, Page(s):2140 - 2145 vol.3
    Cited by:  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (328 KB)

    DC-free runlength-limited codes are studied. Their finite state sequential machine is defined and the achievable rate region is discussed. For the code construction aspect, two general rules are proposed as follows: (1) Always leave suitable redundancy when using the output word which is false in decreasing the running digital sum (RDS) in the absolute value. (2) If state splitting is inevitable, ... View full abstract»

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  • Head of line arbitration in ATM switches with input-output buffering and backpressure control

    Publication Year: 1991, Page(s):347 - 351 vol.1
    Cited by:  Papers (4)  |  Patents (40)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (464 KB)

    The performance of nonblocking input-output-buffered ATM (asynchronous transfer mode) switch architectures with backpressure control is investigated, when operating under different selection mechanisms. The unfairness problem associated with the classical cyclic service mechanism in broadband switches with input and output buffering and backpressure control is explained and three alternative servi... View full abstract»

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  • Field trials of a spread spectrum mobile satellite system using ETS-V satellite

    Publication Year: 1991, Page(s):1366 - 1370 vol.2
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (300 KB)

    The performance of a direct sequence spread spectrum (DS/SS) communication system in land mobile satellite channels is evaluated with experiments. Field test results in the L-band with the ETS-V satellite are presented, in which the use of a multibit-quantized coherent matched filter receiver improves the initial acquisition and the bit error rate performances. The bit error rate characte... View full abstract»

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  • Periodic CCL occurrence frequencies of spreading codes and their influence on slotted CDMA systems

    Publication Year: 1991, Page(s):841 - 845 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (316 KB)

    The OF (occurrence frequency) of CCLs (cross-correlation levels) is introduced to objectively judge CDMA (code division multiple access) code sets. 4-CCL and 5-CCL codes possessing more ideal OFs of CCLs than the Gold code are presented. A new technique utilizing a multivariable Bernoulli process to model the outputs of a CDMA receiver in a slotted system is developed to evaluate BER. It shows the... View full abstract»

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  • Throughput efficiency considerations for optical OPPM

    Publication Year: 1991, Page(s):430 - 433 vol.1
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (180 KB)

    The authors derive a closed-form expression for the cutoff rate of optical overlapping pulse-position modulation (OPPM) systems valid for both the noiseless and the background noise cases and use it to study throughput efficiency for a fixed pulsewidth and data rate. Comparisons are made to pulse-position modulation, which was previously similarly studied, and to on-off keying (OOK). It is seen th... View full abstract»

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  • Outlook for high quality 4 kb/s speech coding for cellular mobile

    Publication Year: 1991, Page(s):1865 - 1868 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (292 KB)

    The author presents a personal view on the outlook for 4-kb/s speech coding for cellular mobile systems in the next two-year time frame. When channel coding of roughly 2.4 kb/s is added to the 4 kb/s of speech information, the total 6.4-kb/s transmission rate will allow the speech signal in any conversation to use only one of six time-division multiple-access slots in any frame instead of the curr... View full abstract»

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  • Effects of circular and linear polarized antennas on wideband propagation parameters in indoor radio channels

    Publication Year: 1991, Page(s):1287 - 1291 vol.2
    Cited by:  Papers (5)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (332 KB)

    Results are presented from an experiment that used a variety of antennas inside two buildings. An important result is that directional circularly polarized (CP) antennas reduce RMS delay spreads when compared with omnidirectional and directional linearly polarized (LP) antennas at identical locations. The variation of RMS delay spread over distances of several wavelengths is also greatly reduced w... View full abstract»

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  • Video traffic smoothing and ATM multiplexer performance

    Publication Year: 1991, Page(s):239 - 243 vol.1
    Cited by:  Papers (8)  |  Patents (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (408 KB)

    The authors report on the performance of a (single-node) multiplexer for transporting variable bit rate video services over ATM (asynchronous transfer mode) networks. Two different cases of cell distribution over a frame period have been considered: random arrival with uniform distribution and burst arrival. It is shown that the network utilization is maximized when sources are uncorrelated and th... View full abstract»

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  • Dynamic threshold implementation of the maximum-likelihood detector for the EPR4 channel

    Publication Year: 1991, Page(s):2135 - 2139 vol.3
    Cited by:  Papers (3)  |  Patents (15)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (376 KB)

    The authors show that the maximum-likelihood Viterbi detector for the binary extended class-4 partial response (EPR4) channel, in additive Gaussian noise, can be implemented using dynamic thresholds. The dynamic threshold method uses eight thresholds, whereas the add-compare-select method uses eight state metrics. The dynamic threshold method has the same performance as the add-compare-select meth... View full abstract»

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  • A noncoherent CPM-detector which uses a reduced set of basis functions

    Publication Year: 1991, Page(s):62 - 66 vol.1
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (352 KB)

    A suboptimum noncoherent detector for partial response CPM (continuous phase modulation) is studied. The number of filters in the filter bank is reduced by using a limited signal space in the CPM detector. It is found that the number of dimensions in the mismatched detector can be considerably reduced. For a quaternary 2RC scheme with h=1/3, the number of filters is reduced from ... View full abstract»

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  • Performance analysis of mobile cellular communication network

    Publication Year: 1991, Page(s):1012 - 1016 vol.2
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (556 KB)

    A cellular mobile communication system is discussed, and the problem of the number of frequency channels required at each cell in a fixed channel assignment scheme in order to keep the probability of call failures below acceptable limits is addressed. The system considered is more realistic than those dealt with in the literature since the authors consider more general motion of the mobiles and al... View full abstract»

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  • Congestion control for connectionless networks via alternate routing

    Publication Year: 1991, Page(s):339 - 346 vol.1
    Cited by:  Papers (3)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (788 KB)

    A congestion control scheme based on alternate routing for connectionless high-speed data networks is presented. In this scheme, if a trunk in the primary path is congested, then a portion of the traffic intended for that trunk is offered to a secondary trunk. The primary path is the shortest distance path in hop count, while the secondary path is at least one hop more than the shortest path. A ke... View full abstract»

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  • DCF reverse modulation type carrier recovery circuit for Rician fading channel

    Publication Year: 1991, Page(s):1360 - 1365 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (352 KB)

    A carrier recovery circuit, the DCF (dual carrier filter) reverse modulation type carrier recovery circuit, is proposed. The circuit performs both a low cycle skipping rate and satisfactory phase tracking characteristics in fast (fDT≃10-2 ) Rician fading channels by employing both narrow and wide bandwidth filters for the DCF reverse modulation carrier ... View full abstract»

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  • Spread-time code division multiple access

    Publication Year: 1991, Page(s):836 - 840 vol.2
    Cited by:  Papers (14)  |  Patents (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (404 KB)

    An alternative code division multiple access (CDMA) scheme to spread spectrum (SS), called spread-time (ST), is proposed for bandlimited multiple access channels. ST-CDMA can be considered the time-frequency dual of SS-CDMA. Implementations are described in which surface acoustic wave (SAW) devices are used to perform the matched filtering or Fourier transformation. A first-order comparison of sig... View full abstract»

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  • Optical transfer networks using distributed XC-MUXs

    Publication Year: 1991, Page(s):1840 - 1844 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (332 KB)

    The authors propose and examine the distribution composition of an XC-MUX (crossconnect multiplexer) with the aim of applying it to an optical transfer network. A numerical analysis confirms that the proposed composition is able to efficiently cope with demand changes on small-scale circuits. A distributed cooperative algorithm, including a self-healing algorithm, is proposed, which can also be ap... View full abstract»

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  • A TDMA satellite communication system for ISDN services-offset QPSK burst modem coupled with high coding gain FEC

    Publication Year: 1991, Page(s):1533 - 1540 vol.3
    Cited by:  Papers (2)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (620 KB)

    The authors propose a time-division multiple-access (TDMA) satellite communication system suitable for integrated services digital network (ISDN) services for both basic interface services and primary interface services. The proposed system offers B-channel transmission lines among telephone offices and subscriber lines for basic and primary interface services. To provide these service economicall... View full abstract»

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  • Wavelength-multiplexed bit synchronization in optical transmission

    Publication Year: 1991, Page(s):423 - 429 vol.1
    Cited by:  Patents (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (540 KB)

    An experiment using wavelength division multiplexing (WDM) for bit synchronization is discussed. At the transmitter, the clock and data bit streams that are generated on lasers of two different wavelengths are wavelength multiplexed together onto the same optical fiber. At the receiver, these signals are wavelength demultiplexed. The demultiplexed clock signal at the receiver is used as a strobe t... View full abstract»

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  • Near optimal spare capacity planning in a mesh restorable network

    Publication Year: 1991, Page(s):2007 - 2012 vol.3
    Cited by:  Papers (47)  |  Patents (35)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (656 KB)

    An algorithm has been developed for the near-optimal assignment of spare capacity in a mesh-restorable network. Test results show that it performs well with respect to an exact linear programming formulation but is also suitable for inspection of the redundancy-restorability tradeoff over its whole domain and is suitable for operational use because it can be applied in an update mode to an existin... View full abstract»

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