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Communications, IEEE Transactions on

Issue 1 • Date January 1983

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Displaying Results 1 - 25 of 28
  • [Front cover and table of contents]

    Publication Year: 1983 , Page(s): 0
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    Freely Available from IEEE
  • Editorial Notes

    Publication Year: 1983 , Page(s): 1
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    Freely Available from IEEE
  • Comments on "Power Spectrum of Angle Modulated Correlated Digital Signals"

    Publication Year: 1983 , Page(s): 160 - 161
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (268 KB)  

    It is pointed out that the sufficiency portion of Theorem 3 in the above paper concerning the existence of discrete spectral components is not proved and, in fact, is not true. A counterexample is provided. View full abstract»

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  • Author's reply

    Publication Year: 1983 , Page(s): 161 - 162
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (143 KB)  

    First Page of the Article
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  • [Back cover]

    Publication Year: 1983 , Page(s): 0
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    Freely Available from IEEE
  • Notes on Spread-Spectrum History

    Publication Year: 1983 , Page(s): 82 - 84
    Cited by:  Papers (4)  |  Patents (9)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (440 KB)  

    This paper presents additional historical information relating to the spread-spectrum history described in [1]. Included here are ties with speech scrambling technology, wide-band matched filter design, stimulus of the WHYN system design by British research, ITT's efforts to protect vital information during World War II, and other miscellaneous notes and references. View full abstract»

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  • Rejection of Pulsed CW Interference in PN Spread-Spectrum Systems Using Complex Adaptive Filters

    Publication Year: 1983 , Page(s): 10 - 20
    Cited by:  Papers (37)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (760 KB)  

    In this paper, the performance of direct sequence QPSK spread-spectrum systems using complex adaptive filters in the presence of pulsed CW interference is analyzed. Both adaptive prediction error filters and adaptive transversal filters with two-sided taps are considered. It is shown that the time constant of the tap weight adaptation in the interference off-interval is usually much greater than t... View full abstract»

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  • Path Rearranging in a Data Switching Network

    Publication Year: 1983 , Page(s): 155 - 157
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (360 KB)  

    Path rearranging results in a 60 percent savings of hardware in a nonblocking 2048-line switch. The blocked connection is freed up by exchanging paths between two middle matrices. Selection criteria for the middle matrices include the incidence of duplicate connections through these matrices. A path rearranging algorithm is derived from the Paull method and implemented in software by the network c... View full abstract»

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  • The Impact of Mismatch on the Performance of Coded Narrow-Band FM with Limiter/Discriminator Detection

    Publication Year: 1983 , Page(s): 28 - 36
    Cited by:  Papers (13)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (792 KB)  

    The performance of uncoded narrow-band FM with limiter/discriminator (L/D) detection over the additive white Gaussian noise channel has received widespread attention [1]-[14] over the years both from simulation and analytical standpoints. By comparison, little or nothing has appeared in the literature for the performance of this modulation/demodulation technique when used together with coding/deco... View full abstract»

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  • Three-Stage Rearrangeable Connecting Networks in the Thermodynamic Limit: Number of Needed Reswitchings

    Publication Year: 1983 , Page(s): 110 - 113
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (344 KB)  

    We show that for sufficiently large systems the needed number of reswitchings is independent of the size and we derive formulas giving the relation between the probability that we have to rearrange and the average number of needed reswitchings. These formulas are backed by computer simulations. Moreover, the packing hunting strategy leads to a greater average number of reswitchings when a call is ... View full abstract»

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  • An Analysis of a Real-Time Transform Domain Filtering Digital Communication System--Part II: Wide-Band Interference Rejection

    Publication Year: 1983 , Page(s): 21 - 27
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (576 KB)  

    Employing the technique of transform domain filtering described in Part I of this paper, a system is presented to detect a binary spread-spectrum signal embedded in a wide-band, stationary, colored Gaussian noise process. Using a specific example of a colored noise process, the performance of the system is analyzed. In addition, a specific technique using surface acoustic wave devices is presented... View full abstract»

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  • On Nonblocking Switching Networks Composed of Digital Symmetrical Matrices

    Publication Year: 1983 , Page(s): 2 - 9
    Cited by:  Papers (19)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (648 KB)  

    Significant advances in semiconductor technology make it possible to construct new components called digital symmetrical matrices, which mix in the same integrated circuit, time and space switching. In this paper, structures of multistage nonblocking networks composed of such matrices are described. The condition under which the network will be nonblocking is formulated, and the relationship betwe... View full abstract»

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  • A Communications System Which Prioritizes the Queues, Service Channels, and Traffic

    Publication Year: 1983 , Page(s): 113 - 118
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (560 KB)  

    A new priority communications protocol has been defined and analyzed. This M/M/C/K system is unique because priorities are assigned not only to the incoming traffic, but also to the queues and the service channels (which may process calls only of an equal or higher priority). This nonpreemptive priority assignment technique significantly improves the grade o... View full abstract»

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  • Modular Verification of Computer Communication Protocols

    Publication Year: 1983 , Page(s): 56 - 68
    Cited by:  Papers (24)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (1272 KB)  

    Programs that implement computer communications protocols can exhibit extremely complicated behavior, and neither informal reasoning nor testing is reliable enough to establish their correctness. In this paper we discuss the application of modular program verification techniques to protocols. This approach is more reliable than informal reasoning, but has an advantage over formal reasoning based o... View full abstract»

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  • Error Sensitivity of CCITT Standard Facsimile Coding Techniques

    Publication Year: 1983 , Page(s): 69 - 81
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (1136 KB)  

    The CCITT has defined Group 3 facsimile apparatus as that which digitally transmits an ISO A4 document over a switched telephone circuit in approximately one minute. Data compression is employed to achieve the reduced transmission time. Study Group XIV of the CCITT has drafted Recommendation T.4 to achieve compatibility between Group 3 facsimile devices. The standard data compression technique spe... View full abstract»

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  • Further Comments on the Characteristics of the Hedeman H-1, H-2, and H-3 Codes

    Publication Year: 1983 , Page(s): 105 - 110
    Cited by:  Papers (2)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (472 KB)  

    This letter clarifies some of the properties of the Hedeman codes and examines their application to band-limited channels. Attention is drawn to the equivalence of H-2 and H-3 to simple linear modulation schemes. All three codes are dc free by virtue of a charge constraint which additionally ensures a minimum distance two (considered as rate one-half codes). The asymptotic error performance at hig... View full abstract»

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  • SS/TDMA Time Slot Assignment with Restricted Switching Modes

    Publication Year: 1983 , Page(s): 149 - 154
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (600 KB)  

    The time-slot assignment problem for a satellite-switched time-division multiple access system where only a restricted set of all possible switching modes is to be used is studied. An efficient algorithm for finding an optimal assignment is proposed. Also, methods for selecting restricted sets of switching modes are presented. View full abstract»

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  • Secret Telephony as a Historical Example of Spread-Spectrum Communication

    Publication Year: 1983 , Page(s): 98 - 104
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (848 KB)  

    The spread-spectrum properties of the X-System for secret telephony developed by Bell Telephone Laboratories for use in World War II are examined. In this system, the bandwidth of the speech signal was reduced by a vocoder, the vocoder signals were sampled and quantized to base six, and a random, never-reused, six-valued key stream was added modulo six to obtain a public message which was undeciph... View full abstract»

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  • Virtual Center Arraying

    Publication Year: 1983 , Page(s): 145 - 149
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (392 KB)  

    One way to increase the amount of data that can be received from weak signal sources (such as spacecraft in the vicinity of the outer planets) is to array several ground antennas in such a way as to increase the total effective aperture of the receiving system. One such method is virtual center arraying (VCA). In VCA, a combined carrier reference is derived at a point that is, conceptually, the ge... View full abstract»

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  • Performance of IJF-OQPSK Modulation Schemes in a Complex Interference Environment

    Publication Year: 1983 , Page(s): 137 - 144
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (448 KB)  

    The error probability (Pe) performance of intersymbolinterference and jitter-free offset-QPSK (IJF-OQPSK) modems in a cochannel and adjacent-channel interference environment is evaluated using a computer simulation technique. Hardware design and experiments have been completed to verify the simulation results. The results indicate that a spectral efficiency of 1.5 bits/s/Hz can be obtai... View full abstract»

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  • Generalized Analysis for the Evaluation of Search Strategy Effects on PN Acquisition Performance

    Publication Year: 1983 , Page(s): 37 - 49
    Cited by:  Papers (34)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (1040 KB)  

    Pseudonoise (PN) coding may be incorporated into the signal structure of a communication system for a variety of reasons. Once present, the PN code must be appropriately acquired before it can be tracked by the receiver. Toward this end various acquisition schemes have been proposed. These schemes include combinations of predetection/postdetection processing and code search strategies. With regard... View full abstract»

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  • Universal Carrier Recovery Loop for QASK and PSK Signal Sets

    Publication Year: 1983 , Page(s): 130 - 136
    Cited by:  Papers (30)  |  Patents (9)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (504 KB)  

    A new carrier recovery loop which applies to quadrature amplitude shift keying (QASK) and phase shift keying (PSK) modulation schemes is presented. This loop is shown to provide significant advantages compared with those already used. Furthermore, the baseband processing of the demodulated signals allows an easy implementation, especially for high-speed digital modems. Both geometrical interpretat... View full abstract»

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  • Reconsideration of "A Fast Computational Algorithm for the Discrete Cosine Transform"

    Publication Year: 1983 , Page(s): 121 - 123
    Cited by:  Papers (21)  |  Patents (5)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (304 KB)  

    Some corrections are made for the original paper "A fast computational algorithm for the discrete cosine transform," 1 which contains some errors of indexes and of multiplication factors. View full abstract»

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  • Experimental Results on Constant Envelope Signaling with Reduced Spectral Sidelobes

    Publication Year: 1983 , Page(s): 157 - 160
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (408 KB)  

    Considerable recent attention has been given to the use of pulse modification to reduce spectral sidelobes in constant envelope data transmission within the "offset" modulation format that includes offset QPSK and MSK. Analytic techniques have been developed which predict probabilistically (without dependence on simulation) the power spectral density that results from pulse modification combined w... View full abstract»

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  • Further Notes and Anecdotes on Spread-Spectrum Origins

    Publication Year: 1983 , Page(s): 85 - 97
    Cited by:  Papers (6)  |  Patents (9)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (1912 KB)  

    This sequel to R. A. Scholtz's monograph of May 1982, in this TRANSACTIONS, adds to the early history of spread-spectrum communications from circa 1900 until about 15 years ago. Relevant to the origins of this field of radio signaling, the following are included in a number of items of quite recent appreciation: the 1930 invention of secret communications featuring spectrum despreading via a local... View full abstract»

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Aims & Scope

IEEE Transactions on Communications focuses on all telecommunications including telephone, telegraphy, facsimile, and point-to-point television by electromagnetic propagation.

 

 

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Robert Schober
University of British Columbia