IRE Transactions on Communications Systems

Includes the top 50 most frequently accessed documents for this publication according to the usage statistics for the month of

  • A Synchronous Communications Receiver for the Military UHF Band

    Publication Year: 1959, Page(s):129 - 133
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (510 KB)

    A synchronous receiver for double-sideband suppressed carrier signals in the 225-mc to 400-mc band is described. The receiver is suitable for voice or data link operation and provides automatic correction of Doppler shifts in the received signal. The "local carrier" oscillator is crystal stabilized at the IF frequency, and electronically tuned by a closed servo loop in which the locallygenerated c... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comparison of PSK vs FSK and PSK-AM vs FSK-AM Binary-Coded Transmission Systems

    Publication Year: 1960, Page(s):87 - 100
    Cited by:  Papers (10)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1301 KB)

    The performance of phase shift keyed (PSK), frequency shift keyed (FSK), PSK amplitude modulation (PSK-AM), and FSK amplitude modulation (FSK-AM), systems are compared for binary coded transmission in the presence of additive white Gaussian noise. This performance is based on the relative probability of error, operating range, required system bandwidth, and system frequency instability. The import... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Sum of Log-Normal Probability Distributions in Scatter Transmission Systems

    Publication Year: 1960, Page(s):57 - 67
    Cited by:  Papers (403)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (938 KB)

    The long-term fluctuation of transmission loss in scatter propagation systems has been found to have a logarithmicnormal distribution. In other words, the scatter loss in decibels has Gaussian statistical distribution. Therefore, in many important communication systems (e.g., FM), the noise power of a radio jump, or hop, has log-normal statistical distribution. In a multihop system, the noise powe... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Group Synchronization for Digital Transmission Systems

    Publication Year: 1962, Page(s):381 - 390
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (939 KB)

    Group synchronization systems with digital feedback are studied, which are particularly applicable for PCM systems. Group synchronization is used to determine the time origin of a sequence of binary signals by finding a specified deterministic pattern from a randomly modulated binary sequence. A statistical analysis is made on the recovery process of synchronization, which is a discrete-time rando... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance of Digital Phase-Modulation Communication Systems

    Publication Year: 1959, Page(s):3 - 6
    Cited by:  Papers (65)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (390 KB)

    This paper analyzes the performance of digital phase modulation systems in Gaussian noise and determines required signal-to-noise ratio as a function of the number of discrete phases and the desired error rate, under conditions of no fading. Both coherent detection with a locally-derived reference carrier and phase comparison detection are considered. The calculations show that multiphase modulati... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Combined Digital Phase and Amplitude Modulation Communication Systems

    Publication Year: 1960, Page(s):150 - 155
    Cited by:  Papers (60)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (599 KB)

    The performance of phase modulation communication systems is investigated for the asymptotic case of a high signal-to-noise ratio. A simple and excellent approximation to the probability of error is derived for both coherent and phase-comparison demodulation. In addition, a simple expression is derived for the asymptotic degradation of phase-comparison demodulation. When the number of bits per sam... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance of Combined Amplitude and Phase-Modulated Communication Systems

    Publication Year: 1960, Page(s):232 - 237
    Cited by:  Papers (36)  |  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (539 KB)

    The performance of two types of digital phase-and amplitude-modulated systems is investigated for the high signal-to-noise ratio region. Approximate expressions for the probability of error and channel capacity of the more optimum of these two systems are compared with corresponding expressions for probability of error and channel capacity for a digital phase-modulated system. It is shown that the... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Coherent Digital Amplitude and Phase Modulation Scheme

    Publication Year: 1962, Page(s):90 - 95
    Cited by:  Papers (50)  |  Patents (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (503 KB)

    In this paper, we present a technique for a combination of amplitude and phase modulation for digital communication. This technique assumes phase coherence between transmitter and receiver. For purposes of analysis, we also assume baud synchronization. The technique involves the simultaneous and independent amplitude modulation of two carriers of the same frequency which are in quadrature with eac... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of SSB Power Amplifiers

    Publication Year: 1959, Page(s):53 - 57
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (525 KB)

    It is well known that one of the critical items in a single sideband (SSB) transmitter is the power amplifier with which are associated the basic problems of distortion, output power and plate dissipation. Tubes are available which may be used either as quasi-linear RF amplifiers operated class AB or B or as gridmodulated amplifiers operated class C. In the class-AB case, the SSB signal is introdu... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance Analysis of a Data Link System

    Publication Year: 1959, Page(s):14 - 24
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1748 KB)

    Because of the increased traffic densities and aircraft speeds contemplated in the near future, the present air-trafficcontrol (ATC) system must be improved by a far more efficient and partially automatic system. To prevent further burden on alreadyburdened voice-communication facilities and frequencies, there is a requirement for more efficient means of transferring information between air and gr... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Propagation of HF and VHF in the Arctic Region

    Publication Year: 1959, Page(s):121 - 125
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (620 KB)

    All the available ionospheric records for stations located north of 60° geographic latitude and for the period 1954 to 1957 were critically analyzed. The F2 region shows two distinct types: one, north of 75° with very little or no diurnal and seasonal variation in the critical frequency; the second, south of 70°N, exhibits diurnal and seasonal variations as well as those correlated ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Simple Methods for Designing Troposcatter Circuits

    Publication Year: 1960, Page(s):193 - 198
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (515 KB)

    As troposcatter circuits come more and more widely into use, there is a need for simple and reasonably accurate design methods for routine use, since the speed of obtaining a suitable design is sometimes of the utmost importance. This paper attempts to present such a method, derived primarily from experimental data, but with occasional reliance upon theoretical calculations. Certain essential desi... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Long Range Subsurface Communication System

    Publication Year: 1961, Page(s):390 - 396
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (715 KB)

    Discussed herein is a point-to-point communication system for ranges in the order of hundreds of miles where the transmitting and receiving equipment, including radiating devices, can be buried deep underground. Results of theoretical analyses and subsequent experimental verifications of various aspects of the communication system have been presented in this paper. Problems on the optimization of ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Theoretical Diversity Improvement in Multiple Frequency Shift Keying

    Publication Year: 1962, Page(s):177 - 184
    Cited by:  Papers (58)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (564 KB)

    Multiple frequency shift keying (MFSK) is a modulation suitable for transmitting digital data under fading conditions. A quantitative analysis of MFSK-with-diversity is presented. The MFSK signals on the several diversity channels are presumed to be perturbed independently by Rayleigh fading and additive white Gaussian noise. Also, it is assumed that fading is slow and that envelope, cross-correla... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Comparison of Digital Communication Systems

    Publication Year: 1960, Page(s):141 - 150
    Cited by:  Papers (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1022 KB)

    Two methods are proposed for comparing the performances of digital communication systems differing in the number of available signals, in bandwidth, in rate of transmission, and in complexity. The systems are ranked on the basis of the probability of correct reception of transmitted messages. The signal durations are adjusted so that the systems have either equal bandwidths or equal rates of trans... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reduction of Quantizing Noise by Use of Feedback

    Publication Year: 1962, Page(s):373 - 380
    Cited by:  Papers (80)  |  Patents (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (669 KB)

    Many information transmission systems use a discrete (digital) channel. Since most input signals are continuous, the conversion cannot be accomplished without an error which, for many cases, may be considered to have the characteristics of white noise. A method has been suggested to reduce this error by using linear feedback around the quantizer to shape the noise spectrum. Each output sample will... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Model of Impulsive Noise for Data Transmission

    Publication Year: 1961, Page(s):130 - 137
    Cited by:  Papers (56)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (731 KB)

    It has often been found more necessary in the engineering of data transmission systems to consider impulsive noise than conventional Gaussian white noise. A model is proposed for the impulsive noise, which describes empirically an amplitude distribution and a time distribution. Because the latter has been described in experimental work principally in terms of error occurrences, the description is ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the Optimum Performance of N-ary Systems Having Two Degrees of Freedom

    Publication Year: 1962, Page(s):185 - 192
    Cited by:  Papers (30)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (649 KB)

    A digital transmission system withnpossible transmitted symbols is considered. If the time between transmitted symbols is T0seconds and the bandwidth isW, thenpossible symbols correspond tonvectors in a2WT_{0}dimensional signal space. This paper considers the theoretical properties of a class of digital systems where the signal spac... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Predetection Diversity Combining with Selectively Fading Channels

    Publication Year: 1962, Page(s):32 - 42
    Cited by:  Papers (83)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (859 KB)

    The effective use of predetection (or IF) linear combining of diversity channels requires that all frequency components be added in = phase. In view of the time-variant phase characteristics of fading channels, some form of instantaneous phase correction must be provided prior to the diversity combining so that proper in-phase addition will result. If the instantaneous fading is not uniform over t... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effects of Impulse Noise on Digital Data Transmission

    Publication Year: 1961, Page(s):355 - 361
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (894 KB)

    This paper presents the basic characteristics of impulse noise and its effects on various types of binary data transmission systems. The sources and properties of such impulsive noise, in contrast to Gaussian noise, are discussed. A method is described for the experimental comparative evaluation of bit error rates in the presence of additive impulse noise. The method is shown to permit unique comp... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Jamming Vulnerability of Communication Systems

    Publication Year: 1961, Page(s):226 - 232
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (699 KB)

    This paper presents the procedure for evaluating the jamming vulnerability of a communication system. The factors considered include system performance under laboratory conditions, characteristics of transmission channels, power and transmitter design of jammer, and the costs of desired communication and jamming systems. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Detection and Information Rate of Telegraphic Signals

    Publication Year: 1961, Page(s):70 - 76
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (785 KB)

    "Detection" in the title of this paper is used in the sense of decision-making, rather than demodulation. The ideal communication rate for a physical channel is provided by Shannon's formulaC leq W log(1 + P/N), and for a binary symmetric channel the theoretical amount of information per digit isI = 1 + p log p + q log q, wherepis probability of error per digit and... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Military Radio Communications Equipment Cost-Design Relationships

    Publication Year: 1960, Page(s):203 - 206
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (445 KB)

    A method is presented for determining the relationships between the "costs" (size, weight, dollars) and the electrical characteristics (frequency, bandwidth, input power, output power, atenna gain) of radio equipment used in military communications systems. The compilation of pertinent data is described, and a series of empirical "trade-off" curves displaying cost-design relationships as they exis... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Real-Time Data Transmission System

    Publication Year: 1959, Page(s):201 - 205
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (520 KB)

    A real-time data transmission system was designed for and installed at the Atlantic Missile Range. This system is used to transmit the digital range, azimuth, and elevation coordinates from remotely located AN/FPS-16 radars into the Range Safety IBM 704 Computer at Cape Canaveral, Fla. The radar data is transmitted at a 10PPS rate and is used in the computation of a predicted impact point ten time... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Experimental Automatic Communication System for Air Traffic Control

    Publication Year: 1959, Page(s):71 - 76
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (554 KB)

    The "Experimental Automatic Ground/Air/Ground Communication System (AGACS)" under development for the Bureau of Research and Development, Federal Aviation Agency, will provide a two-way traffic control data link permitting automatic mechanized communication for essential routine flight information between the air and ground environments. The system selected is operable in both VHF and UHF aircraft... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the Optimum Detection of Digital Signals in the Presence of White Gaussian Noise-A Geometric Interpretation and a Study of Three Basic Data Transmission Systems

    Publication Year: 1962, Page(s):336 - 372
    Cited by:  Papers (59)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2976 KB)

    This paper considers the problem of optimally detecting digital waveforms in the presence of additive white Gaussian noise. A technique for representing the transmitted signals and the additive noise which leads to a geometric interpretation of the detection problem is presented on a tutorial level. Subsequently, this technique is used to derive the optimum detector for each of three basic data tr... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The role of telecommunication in air transport

    Publication Year: 1956, Page(s):20 - 22
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (294 KB)

    The author takes an objective look at how telecommunication has been, is, and will probably be used by air transportation. It is recommended that private enterprise implement the communication framework for use jointly by the government and nongovernment agencies. The feasibility of that rrecommendation appears evident; existing land line plant facilities of the nation furnished by private enterpr... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Routing Procedures in Communications Networks-Part I: Random Procedures

    Publication Year: 1962, Page(s):322 - 329
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (883 KB)

    A study is made of possible routing procedures in military communications networks in order to evaluate these procedures in terms of future tactical requirements. In Part I this study is devoted to procedures involving random choices. In such networks each message path is essentially a random walk. Estimates of the average traverse time of each message and average traffic flow through each node ar... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Air Traffic Control in the Jet Age

    Publication Year: 1956, Page(s):34 - 47
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1200 KB)

    An effective forward step in terminal area air traffic control has been accomplished by development and installation of Radar Approach Control (RAPCON) Center and control tower prototype facilities described. Esoteric complexes detailed provide airport and approach controllers with radar and communication implementation of manual aids to jet and propeller driven traffic control procedures and tech... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • System Engineering

    Publication Year: 1956, Page(s): 1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (135 KB)

    Summary form only given. All large undertakings must be divided and subdivided into parts of suitable size tor application of group and individual effort if they are to be brought to successful conclusion. This, at necessity, develops specialists who are expert in relatively narrow fields. Communication engineering is no exception to this rule and we find an ever-growing specialization with many e... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Synchronous Communications

    Publication Year: 1957, Page(s):99 - 105
    Cited by:  Papers (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (824 KB)

    It can be shown that present usage of amplitude modulation does not permit the inherent capabilities of the modulation process to be realized. In order to achieve the ultimate performance of which AM is capable synchronous or coherent detection techniques must be used at the receiver and carrier suppression must be employed at the transmitter. When a performance comparison is made between a synchr... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High-Speed Frequency-Shift Keying of LF and VLF Radio Circuits

    Publication Year: 1957, Page(s):29 - 42
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1904 KB)

    Present VLF transmitters are limited in transmission speed to approximately 20 words per minute because of the bandwidth limitations of the High-Q antenna circuit. To permit an increase in transmission speed, a unique method has been developed which makes use of the variation of reactance of the antenna circuit in synchronism with frequency shift modulation of the carrier. The method makes possibl... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reliability and Economics of Telecommunication Systems

    Publication Year: 1958, Page(s):22 - 26
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (404 KB)

    The paper evaluates telecommunication system functional reliability, based on average failure rates, and formulates operational reliability that also takes into consideration the duration of breakdowns and the time necessary for their repair. Various system arrangements are considered. Optimum maintenance methods are determined from operational reliability and, using the inventory-method, expected... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Theory of FM Demodulation with Frequency-Compressive Feedback

    Publication Year: 1962, Page(s):226 - 245
    Cited by:  Papers (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2307 KB)

    The application of frequency-compressive feedback around an amplitude-insensitive FM demodulator promises important reductions of distortion and noise sensitivity in the demodulation of wide-band FM signals. In this paper, the basic theory of FM demodulation with frequency-compressive feedback (FCF) is presented after a brief discussion of the concept of noise threshold and of the usefulness of th... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Analog Multiplier Using Two Field Effect Transistors

    Publication Year: 1962, Page(s):311 - 317
    Cited by:  Papers (5)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (569 KB)

    A four-quadrant analog multiplier is described which uses the variable channel conductance properties of the field effect transistor. This multiplier is characterized by moderate accuracy, high speed and circuit simplicity. As such, it may be useful in many applications where speed is important but a high degree of accuracy is not. Such an application is found in synchronous detection circuits des... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Simple Decoders and Correlators for Cyclic Error-Correcting Codes

    Publication Year: 1962, Page(s):284 - 290
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (690 KB)

    Several promising techniques for instrumenting error-correcting codes are briefly described. These techniques consist of digital decoders for the binary symmetric channel and for the binary erasure channel, and analog word correlators for variable and low bit-rate operation. The performance pay-off of these techniques in comparison to their implementation simplicity indicates the possibility of in... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Doppler Phenomena in Space Communications

    Publication Year: 1959, Page(s):25 - 30
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (538 KB)

    The Doppler phenomenon is studied under spaceflight conditions. These conditions impose restrictions, and introduce influences which otherwise are of negligible importance. Examples of undesired effects of the Doppler shift in space communications and of applications for useful purposes are given. General relations are derived for the Doppler shift which permit consideration of the space-flight co... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Microwave System Engineering Using Large Passive Reflectors

    Publication Year: 1962, Page(s):304 - 311
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1154 KB)

    This paper will provide the microwave engineer with the basic techniques of microwave system engineering using large passive reflectors and will outline the many advantages of their use. Small passive reflectors of the "periscope type" have been used for many years on microwave systems. Large passive reflectors have also been used but to a much lesser degree. Large passives may be used at intermed... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Mutual Interference in Communication Equipment Can Be Reduced

    Publication Year: 1961, Page(s):462 - 469
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (955 KB)

    The application of well-known techniques in the re-examination of existing systems, aided by interference charts to identify areas of greatest vulnerability, will prolong the useful life of present equipment and guide designers of future systems to meet advancements in the state of the art. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Linearity and Intermodulation in High-Power Tuned Amplifiers

    Publication Year: 1962, Page(s):219 - 220
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (244 KB)

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Laboratory Comparison of Maximal-Ratio Combiners and Optimal Selectors for Fading HFSK Channels

    Publication Year: 1961, Page(s):320 - 321
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (170 KB)

    Experimental results are described to demonstrate the superiority of a maximal ratio combiner (or ratio squarer) over an optimal selector in the reception of fading HFSK signals. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • 50-kw Antenna Switching System

    Publication Year: 1959, Page(s):295 - 301
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2002 KB)

    There are many HF radio installations today that illustrate the need for an improved antenna switching technique. Today there is a growing requirement to connect rapidly any one of several 50-kw transmitters to any one of many antennas. An antenna switching system must be broad-band, convenient to use, fast, safe for operating personnel, and free of appreciable impedance discontinuities. This pape... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Constant-Ratio Code and Automatic-RQ on Transoceanic HF Radio Services

    Publication Year: 1960, Page(s):72 - 75
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (506 KB)

    Historical development, of present-day commercial teleprinter services, is briefly tabulated according to dates of significant advances. The 7-unit form of basic constant-ratio code is given, and its advantages explained; indicative values of improvement are tabulated. A general description of the Automatic-RQ method and system-rather than specific designs-is given. Commercial application and grow... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Results from a Three-Hop Tropospheric Scatter Link in Norway with Parallel Operations on 900 mc and 2200 mc

    Publication Year: 1960, Page(s):20 - 26
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (631 KB)

    A three-hop troposcatter system in Norway with simultaneous operation at 900 mc and 2200 mc is described briefly. From measurements on a 360-km hop in the period October 1957 to June 1958, it is concluded that 1) the monthly amplitude distributions are approximately Gaussian, and the 1-minute amplitude distributions are approximately of the Rayleigh type, 2) the signals are generally considerably ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Transmitter Power Control in Two-Way Communications System

    Publication Year: 1960, Page(s):48 - 56
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1069 KB)

    A typical scatter communications loop consists of two sites, each having transmitters and receivers operating simultaneously over a two-way microwave loop. In tropospheric scatter systems, disturbances in the microwave paths produce dynamic fading of RF signal levels at the receivers. To achieve high system reliability, the current practice is to continuously transmit high power, adequate to maint... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • AFC for Frequency Hopping Systems

    Publication Year: 1962, Page(s):202 - 208
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (696 KB)

    An AFC system has been developed for stabilizing the frequency of a voltage-tunable oscillator near any one of many discrete frequencies. A delay line takes the place of the conventional cavity in the discriminator. The discrete steps correspond to the electrical length of the delay line, e.g., 2 Mc in the S-band system reported herein. Slow frequency fluctuations inherent in the oscillator are re... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Intermodulation Distortion and Efficiency Analysis of Multicarrier Repeaters

    Publication Year: 1960, Page(s):68 - 71
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (426 KB)

    Under suitable conditions a common RF repeater may be used to amplify a number of modulated carriers. The basic limitations are efficiency and intermodulation distortion introduced within the frequency band of any modulated carrier wave by the other modulated carrier waves. Any repeater contains a high-power tube for which the output-input characteristic has nonlinearities that introduce a certain... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comparative Performance of Digital Data Transmission Systems in the Presence of CW Interference

    Publication Year: 1962, Page(s):169 - 177
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (911 KB)

    During the last decade there has been a considerable amount of work done on the analysis of digital data transmissions in an interference environment. With few exceptions, the type of additive interference considered is normal noise. This paper treats the case where the interference consists of CW that falls within the pass band of the receiver. The results obtained can also be utilized to ascerta... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Use of Optical Frequencies for Space Communication

    Publication Year: 1960, Page(s):164 - 168
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (687 KB)

    The spectrum from the infrared through the visible to gamma rays has been surveyed for signalling from Earth or an Earth satellite to a spaceship at planetary distances. The best region for signalling from a satellite vehicle appears to be from 2000 to 400 angstroms. One information bit per second could be sent for a distance many times the diameter of the solar system. If the source is to be on t... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Influence of Fading Spectrum on the Binary Error Probabilites of Incoherent and Differentially Coherent Matched Filter Recievers

    Publication Year: 1962, Page(s):160 - 168
    Cited by:  Papers (106)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (820 KB)

    Previous derivations of the influence of fading on the error probabilities of binary data transmission systems have assumed that the fading rate is so slow that fluctuations within a bit may be ignored. This slow fading assumption is removed in the present paper which derives general expressions for the binary error probabilities of incoherent and differentially coherent matched filter receivers e... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

This Transactions ceased publication in 1962. The current retitled publication is  IEEE Transactions on Communications.

Full Aims & Scope