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Military Communications Conference, 1989. MILCOM '89. Conference Record. Bridging the Gap. Interoperability, Survivability, Security., 1989 IEEE

Date 15-18 Oct. 1989

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Displaying Results 1 - 25 of 169
  • MILCOM 89. Bridging the Gap. Interoperability, Survivability, Security. Conference Record. 1989 IEEE Military Communications Conference (Cat. No.89CH2681-5)

    Publication Year: 1989
    Request permission for commercial reuse | PDF file iconPDF (157 KB)
    Freely Available from IEEE
  • Truncation effects in Viterbi decoding

    Publication Year: 1989, Page(s):541 - 545 vol.2
    Cited by:  Papers (10)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (288 KB)

    Practical Viterbi decoders often fall significantly short of full maximum likelihood decoding performance because of survivor truncation effects. In the present work the authors study the tradeoff between truncation length and performance loss for the two most common variations of Viterbi's algorithm: best-state decoding (BSD) and fixed-state decoding (FSD). It is found that FSD survivors should b... View full abstract»

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  • 8-PSK trellis codes on Rayleigh channel

    Publication Year: 1989, Page(s):536 - 540 vol.2
    Cited by:  Papers (8)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (276 KB)

    Trellis-coding techniques are considered as a means of improving the reliability of 8-PSK (phase-shift keying). It is shown that the combination of a rate 2/3 convolution code and 3-b interleavers provides a good modulation/coding method for the Rayleigh channel. The author proposes a suboptimal coded system that combines a regular convolutional code, bit interleaving, and an appropriate decoding ... View full abstract»

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  • Enhanced network survivability through balanced resource criticality

    Publication Year: 1989, Page(s):682 - 687 vol.3
    Cited by:  Papers (6)  |  Patents (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (356 KB)

    The authors describe two entropy-based measures that can be used to assess how close a network design comes to being maximally survivable: normalized node entropy (NNE) and normalized link entropy (NLE). Maximum survivability is achieved when the enemy cannot identify critical points of failure and must remove a maximum number of nodes/links before the network becomes disconnected. The normalized ... View full abstract»

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  • Diversity and coding for an interference model

    Publication Year: 1989, Page(s):531 - 535 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (284 KB)

    An information-theoretic analysis of two interference models, one introduced in the work of D. Chase and L.H. Ozarow (IEEE Trans. Commun., vol.COM-27, p.441-8, Feb. 1979) and the other, the conventional model, is given. The computational cutoff rate is computed for the two channel models for BFSK (binary-frequency-shift keying) on conventional receivers using L diversity and square-law co... View full abstract»

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  • Throughput optimization in single commodity slotted ALOHA multi-hop packet radio networks

    Publication Year: 1989, Page(s):377 - 382 vol.2
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (396 KB)

    The authors investigate the maximum throughput that can be supported between a pair of nodes in a multihop packet radio network using slotted ALOHA. The optimization problem can be formulated as a nonlinear programming problem. The authors study different topologies where source and destination are connected with a number of independent paths and consider the cases in which the flow from source to... View full abstract»

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  • On air defense communications network connectivity

    Publication Year: 1989, Page(s):677 - 681 vol.3
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (308 KB)

    The authors address the issue of communication network survivability and provide a quantitative measure of the time-varying connectivity of space and ground multimedia networks operating in stressed environments. This measure allows comparison of very different network architectures in terms of connectivity. A generic SBR (Space-Based Radar) constellation was selected for study of the communicatio... View full abstract»

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  • GaAs in the military marketplace

    Publication Year: 1989, Page(s):122 - 127 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (432 KB)

    It is noted that, with the advantages (speed and low power) of using GaAs digital integrated circuits, GaAs has now become the technology of choice for high-performance systems. Over the past three years, improvements in processing, manufacturing, and design methodology have been able to overcome the major barriers to the acceptance of this technology, that is yield, cost, stable sources of supply... View full abstract»

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  • Diversity reservation ALOHA

    Publication Year: 1989, Page(s):402 - 407 vol.2
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (524 KB)

    A multiaccess protocol suitable for packet-switched satellite broadcast channels is considered. The proposed protocol, called diversity reservation ALOHA (DRA), combines the essential features of announced retransmission random access (ARRA), reservation ALOHA, and diversity ALOHA to achieve the goals of improved delay-throughput characteristics and high channel utilization. Two versions of DRA pr... View full abstract»

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  • Meteor scatter signal footprint variation with range, power margin and time of day

    Publication Year: 1989, Page(s):423 - 427 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (336 KB)

    It is emphasized that consideration of meteor scatter to provide LPI (low probability of intercept) communications must include a complete understanding of the relevant conditions and assumptions. Given these assumptions, trail footprint analysis can be used to predict intercept probability versus receiver location or, similarly, diversity spacing for multiple receivers to optimize link performanc... View full abstract»

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  • Shipboard fiber optic transmission media (cables)

    Publication Year: 1989, Page(s):235 - 241 vol.1
    Cited by:  Papers (1)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1124 KB)

    The authors present some important technical advantages that can be realized by implementing fiber optics aboard ships. They emphasize the problem of cable clutter aboard ships and the advantages of weight reduction gained through the reduction of copper cables. They also describe a new shipboard fiber-optic cable series designed to meet recently published US Navy specifications View full abstract»

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  • A robust adaptive filtering algorithm with variable step size

    Publication Year: 1989, Page(s):526 - 530 vol.2
    Cited by:  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (244 KB)

    The authors present a variable-step adaptive filtering algorithm (VS-NLMS) that is robust in the presence of interference. An estimated cross-correlation coefficient between the input reference signal and the error signal is used as the variable step size. Compared with the conventional fixed-step adaptive filtering algorithm (NLMS), the VS-NLMS algorithm can achieve much lower misadjustment noise... View full abstract»

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  • A technique for detecting unknown weak signals in noise that is not additive white Gaussian

    Publication Year: 1989, Page(s):370 - 376 vol.2
    Cited by:  Papers (12)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (376 KB)

    A general spectrum-analysis-based approach to the problem of detecting the presence of unknown weak signals in noisy observations is developed. The weak signal assumption enables exploitation of familiar results from the theory of local optimality, from which correlation-based detectors for the presence of known weak signals in additive independent and identically distributed (IID) noise have been... View full abstract»

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  • Simulation of serial acquisition in fast-frequency-hop system

    Publication Year: 1989, Page(s):880 - 884 vol.3
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (348 KB)

    A system for acquiring synchronization in a 16000-hop/s covertly coded frequency-hop one-way communications link is simulated to investigate the effect of interference and fading on the acquisition time and the probability of missing the genuine signal. The system is to use 7000 channels spaced at 25 kHz. The information rate is 1 b/hop. The serial search technique is used for coarse acquisition, ... View full abstract»

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  • A class of adaptive routing and link assignment algorithms for large-scale networks with dynamic topology

    Publication Year: 1989, Page(s):671 - 676 vol.3
    Cited by:  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (456 KB)

    The authors present novel algorithms for adaptive routing and link assignment, which can be used in a large-scale network (1000-10000 nodes) with dynamic topology and stress. Special attention was given to performance (delay, throughput, and survivability) and implementation cost issues as the size of the network grows. These costs are controlled by a logical partitioning of the network into areas... View full abstract»

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  • A method to analyze interference from frequency hopping radios and its application to the PROFFAR cosite filter for the Swedish army

    Publication Year: 1989, Page(s):928 - 934 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (440 KB)

    A computerized method (called SIGFRID) to simulate the amount of frequency-hopping interference in a receiver subjected to a number of interfering transmitters in a cosite situation was developed a few years ago. The method handles full scenarios, including friendly and hostile distant transmitters, jammers, ambient noise, and propagation characteristics. Modeling of important receiver and transmi... View full abstract»

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  • Multilevel secure mixed-media communication networks

    Publication Year: 1989, Page(s):117 - 121 vol.1
    Cited by:  Papers (3)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (520 KB)

    A communication system architecture that provides security for different groups of users while allowing each group access to a common pool of network and transmission assets is presented. Transmission assets can be mixed, operating with different propagation media and network protocols. Placement of encryption processes required to support security services is of particular interest. Support of se... View full abstract»

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  • Value-based multiplexing of time-critical traffic

    Publication Year: 1989, Page(s):395 - 401 vol.2
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (556 KB)

    The concept of message `value' is used as a means of measuring performance. A `value function' is defined for each message and represents its value to the intended recipient as a function of the total delay in transporting it. These value functions not only incorporate the usual notions of relative priority (i.e. importance) between different messages but also capture the time-critical characteris... View full abstract»

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  • Adaptive trellis coded modulation for bandlimited meteor burst channels

    Publication Year: 1989, Page(s):418 - 422 vol.2
    Cited by:  Papers (9)  |  Patents (26)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (360 KB)

    The author investigates the throughput performance of an adaptive information-rate technique on the bandlimited meteor burst channel. It is shown that an adaptive technique that uses trellis-coded modulation (TCM) can increase throughput over the conventional constant-rate modem by more than a factor of 3. An expression for the theoretical information capacity of the bandlimited meteor burst chann... View full abstract»

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  • Adaptive forwarding and routing in frequency-hop spread-spectrum packet radio networks with partial-band jamming

    Publication Year: 1989, Page(s):230 - 234 vol.1
    Cited by:  Papers (2)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (516 KB)

    The authors consider adaptive protocols for routing around localized partial-band jamming in a frequency-hop (FH) packet radio network. With such protocols, a radio is permitted to modify its normal routing procedures according to local information. A computer program has been developed to simulate an FH packet radio network with partial-band jamming and interference due to other FH and narrowband... View full abstract»

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  • An adaptive clutter and interference suppression with a minimum residue noise power

    Publication Year: 1989, Page(s):521 - 525 vol.2
    Cited by:  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (380 KB)

    The author presents an adaptive technique for the suppression of clutter and interference in environments where no a priori knowledge about the target or the clutter and interference statistics is available. The adaptive processor generates the average weight vector, in the sense of minimum-residue-noise-power, on the basis of the injected noise-level vector in the weight control algorithm. The se... View full abstract»

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  • Application of simulation based analysis to receiver design for operation in impulsive atmospheric noise

    Publication Year: 1989, Page(s):570 - 576 vol.2
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (516 KB)

    The author illustrates a Monte-Carlo procedure that simulates impulsive noise bursts by using a set of characteristics that represents a realistic range of values. It is expected that many non-Gaussian varieties of noise may be dealt with numerically in a similar manner, following experimental determinations of the most appropriate parameter values for use in the noise model. A limited sample case... View full abstract»

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  • Limitations on the detectability of spread-spectrum signals

    Publication Year: 1989, Page(s):364 - 369 vol.2
    Cited by:  Papers (2)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (348 KB)

    The standard analysis of the radiometric detectability of a spread-spectrum signal assumes a background of stationary white Gaussian noise whose power spectral density can be measured very accurately. This assumption yields a fairly high probability of interception, even for signals of short duration. Using a generalization of the detection scenario, the authors demonstrate that realistic detectio... View full abstract»

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  • A routing scheme for hierarchically structured LAN/WAN networks

    Publication Year: 1989, Page(s):214 - 218 vol.1
    Cited by:  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (452 KB)

    The authors propose a routing scheme for multiorganizational networks structured hierarchically in a two-level LAN/WAN (local-area network/wide-area network) configuration. The targeted networks, besides being hierarchical, are small in size than the public internets. These two characteristics play a key role in identifying suitable routing mechanisms. The authors propose a simple area routing alg... View full abstract»

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  • A rapid acquisition of PN sequences for DS/SS systems based on a truncated SPRT

    Publication Year: 1989, Page(s):875 - 879 vol.3
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (324 KB)

    The authors study a rapid coherent acquisition scheme, using a truncated sequential-probability-ratio test (TSPRT), for direct-sequence-spread spectrum (DS/SS) systems. Since the partial correlation of pseudonoise (PN) sequences is difficult to characterize, the worst-case partial correlation is considered. Linearized bounds of the partial correlation are used for designing the TSPRT so that the r... View full abstract»

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