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

15-18 Oct. 1989

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Displaying Results 1 - 25 of 169
  • Adaptive HF for voice and data

    Publication Year: 1989
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (42 KB)

    Summary form only given. The authors describe an adaptive HF system for voice and video. The system uses information obtained from a link quality analysis and/or ionospheric soundings to determine the appropriate link and frequency over which to communicate. In addition, the system can be frequency hopped, thereby reducing the probability of being jammed. The improved performance obtained using fr... View full abstract»

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  • 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
  • MSE routing algorithm comparison

    Publication Year: 1989, Page(s):42 - 46 vol.1
    Cited by:  Papers (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (384 KB)

    The US Army's Mobile Subscriber Equipment (MSE) communications system uses a flood search algorithm for routing calls. This procedure automatically finds alternate paths to the call destination during the search and requires only a directory of local subscribers to be maintained at each node. Recently, it was suggested that two other routing methods, restricted flood search and hybrid routing, wou... View full abstract»

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  • Performance of an order statistic based diversity combining M -ary frequency-hopping system in a partial-band jamming environment

    Publication Year: 1989, Page(s):11 - 15 vol.1
    Cited by:  Papers (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (448 KB)

    An order-statistic-based combining technique is evaluated for fast frequency hopping spread spectrum receivers operating in the presence of partial-band noise (PBN) jamming. The method replaces the linear combining receiver with an outlier-resistance estimator based on order statistics. A practical algorithm that sums all but the largest of the received hops is advocated, and a diversity combining... View full abstract»

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  • Adaptive rate error control through the use of diversity combining and majority logic decoding in a hybrid-ARQ protocol

    Publication Year: 1989, Page(s):558 - 563 vol.2
    Cited by:  Papers (1)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (368 KB)

    The author demonstrates an adaptive rate coding system based on the majority logic decoding of convolutional codes. The proposed system retains the high-data-rate capability of FEC (forward error correction) majority logic decoders while providing an adaptive code rate and a significant improvement in error protection through the incorporation of diversity combining and hybrid-ARQ (automatic repea... View full abstract»

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  • Bounded delay routing for real-time communication in tactical radio networks

    Publication Year: 1989, Page(s):37 - 41 vol.1
    Cited by:  Papers (1)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (364 KB)

    To deal with the need for availability and real time response, military communication has employed protocols with deterministic service such as that found in SS/TDMA (spread-spectrum/time-division multiple-access) control of satellite links, or T1, T2, or T3 ground relay optic fibers. The author addresses the problem of providing network layer communication with deterministic service in multihop r... View full abstract»

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  • A new pseudo-random interleaving for antijamming applications

    Publication Year: 1989, Page(s):6 - 10 vol.1
    Cited by:  Papers (1)  |  Patents (31)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (344 KB)

    The authors define a pseudorandom interleaver whose minimal distance is nearly the same as that of a periodic interleaver of the same size. The distance between two symbols of the same code word is not constant, and symbols are selected pseudorandomly inside the interleaving register. This makes it proof against attacks by intelligent jammers. The interleaver uses a matrix read and written at the ... View full abstract»

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  • Packet recovery and error correction in high-speed wide-area networks

    Publication Year: 1989, Page(s):551 - 557 vol.2
    Cited by:  Papers (10)  |  Patents (53)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (540 KB)

    The author presents a novel technique for reducing packet loss rate in high-speed wide-area networks in which the BER (bit-error rate) is low. Grouping packets into blocks and adding a packet that computes parity over bits of all packets in a block allow a data recipient to reconstruct any single packet in a block, using the other packets and the block parity packet. The missing packet is identifi... 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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  • Blind separation and capture of communication signals using a multitarget constant modulus beamformer

    Publication Year: 1989, Page(s):340 - 346 vol.2
    Cited by:  Papers (48)  |  Patents (30)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (560 KB)

    A multitarget least-squares CMA (constant modulus algorithm) that blindly adapts a narrowband beamformer to separate and capture multiple communication signals by exploiting only the low modulus variation of the communication waveforms is presented. It is shown that the algorithm can detect and classify transient and nontransient communication signals on the basis of modulus variation and extract ... View full abstract»

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  • The use of MIL-STD-188-141A in HF data networks

    Publication Year: 1989, Page(s):75 - 79 vol.1
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (328 KB)

    HF data communication has become more reliable and user friendly with the advent of first-generation HF automatic link establishment (ALE) equipment. The newly released MIL-STD-188-141A established a more robust, flexible, and interoperable ALE protocol, and resulted in a second generation of ALE equipment. With the addition of a supervisory network controller to the ALE equipment, advanced networ... View full abstract»

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  • Performance of fast frequency hopped noncoherent MFSK with a fixed hop rate under worst case jamming

    Publication Year: 1989, Page(s):30 - 36 vol.1
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (492 KB)

    The authors evaluate the throughput performance of FFH/MFSK (fast frequency hopping/M-ary frequency-shift keying) with a fixed hop rate for both uncoded and coded systems. The performance criterion used is a throughput measure, that is information rate sustained by a system for a given bit-error rate normalized by the hop rate. It is shown that the performance can be greatly improved thro... View full abstract»

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  • Channel access protocols for half duplex satellite terminals

    Publication Year: 1989, Page(s):463 - 469 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (488 KB)

    The author shows why carrier-sense multiple access (CSMA) is unusable with the combination of half duplex terminals and the success/failure channel. Distributed round-robin and distributed reservation protocols are given as examples of two classes of usable protocols. The author shows how to convert the success/failure channel to a something/nothing channel-(a channel in which accesses can be dist... View full abstract»

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  • Imperfect jamming state information generators for coded FH/MFSK under partial-band noise jamming

    Publication Year: 1989, Page(s):1 - 5 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (304 KB)

    Three imperfect jamming state information (JSI) generators for coded, memoryless, noncoherent, frequency-hopped M-ary frequency-shift-keying (FH/MFSK) systems under partial-band noise jamming (PBNJ) are introduced. These are then compared with respect to the bit-energy-to-jamming-noise power spectral density ratio (E b/NJ) required to achieve cutoff... View full abstract»

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  • New results on soft-decision decoding of block codes

    Publication Year: 1989, Page(s):546 - 550 vol.2
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (464 KB)

    Generalized-minimum-distance (GMD) decoding is a soft-decision decoding algorithm that uses an acceptance criterion and a sequence of attempts at errors-and-ensures decoding in order to find the code work that is closest in generalized distance to the received vector. In the present work the authors develop a new acceptance criterion that gives better performance for GMD decoding that can be obtai... 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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  • The effect of spectral shaping on the probability of detection of a DS-SS in the presence of CW interference

    Publication Year: 1989, Page(s):335 - 339 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (288 KB)

    Direct sequence spread spectrum (DS-SS) modulation is employed in digital communication systems to provide low probability of detection and reduce the effects of interference. A radiometer can be used to detect the presence of the SS signal within some bandwidth. The presence of CW (continuous wave) interference severely degrades the performance of the radiometer. An interference excision filter c... View full abstract»

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  • A distributed time-slot assignment protocol for mobile multi-hop broadcast packet radio networks

    Publication Year: 1989, Page(s):70 - 74 vol.1
    Cited by:  Papers (29)  |  Patents (19)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (484 KB)

    A distributed time-slot-assignment protocol for a mobile multihop broadcast packet radio network, using time division multiple access channel access, virtual circuit switching, and minimum hop path routing is developed. The protocol eliminates the single-point failure mode of centralized network management and the delays of centralized processing. It is applicable to the user-to-user communication... View full abstract»

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  • Performance of Viterbi's ratio threshold receiver against mixed jamming

    Publication Year: 1989, Page(s):25 - 29 vol.1
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (200 KB)

    A performance analysis is presented for a coded FH/MFSK (frequency-hopping/M-ary frequency-shift-keying) system under a combination of tone jamming and full-band-noise jamming (FBNJ). A maximum likelihood metric former with Viterbi's ratio threshold techniques is assumed to support the decoder in the system. It is shown that the most efficient FBNJ portion of the total jamming power depen... View full abstract»

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  • Analog filter design for improved performance in an atmospheric noise environment

    Publication Year: 1989, Page(s):577 - 580 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (224 KB)

    It is shown that several transitional low-pass characteristics can be converted accurately to realizable bandpass crystal filters for the very narrowband case (0.17% relative bandwidth and smaller). Ordinary design techniques such as Dishal's are applicable up to 5% relative bandwidth; but beyond that, up to about 50%, special techniques like bandwidth scaling and center frequency translation of a... View full abstract»

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  • A man-portable X-band terminal system

    Publication Year: 1989, Page(s):457 - 462 vol.2
    Cited by:  Papers (1)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (492 KB)

    The authors outline a concept for a man-portable X-band terminal system that would operate via DSCS (Defense Satellite Communication System) III and other nonprocessing SHF (super high-frequency) satellites. The system data rate and capacity are analyzed, and a design concept that will support 75-2400-b/s data and 2400-b/s digital voice communications is discussed. A demand-assigned multi... View full abstract»

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  • On the design of performance-constrained survivable networks

    Publication Year: 1989, Page(s):663 - 670 vol.3
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (408 KB)

    The authors describe a network design algorithm that combines standard traffic flow analysis with previously ignored topological survivability considerations. The proposed approach uses a version of the cut-saturation algorithm proposed by Gerla et al. (1974) modified to include considerations for survivability in the process of adding and deleting link resources to meet specified throughput goals... View full abstract»

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  • An automatic high frequency radio network for the Military Airlift Command

    Publication Year: 1989, Page(s):90 - 94 vol.1
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (336 KB)

    The authors describe the initial design of an automatic high-frequency (HF) radio network for the Military Airlift Command (MAC). The network design incorporates new technology that will make HF communications more reliable. The network uses the Automatic Communications processor (ACP) developed for MAC to perform adaptive frequency selection and automatic link establishment (ALE). The MAC network... View full abstract»

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  • A tone-aided dual vestigial sideband system for digital communications on fading channels

    Publication Year: 1989, Page(s):709 - 714 vol.3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (404 KB)

    A spectrally efficient tone-aided dual vestigial sideband (TA/DVSB) system for digital data communications on fading channels is presented and described analytically. This PSK (phase-shift-keying) system incorporates a feed-forward, tone-aided demodulation technique to compensate for Doppler frequency shift and channel- induced, multipath fading. In contrast to other tone-in-band-type systems, rec... View full abstract»

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  • 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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