Download or read book Equipment Characteristics and Their Relation to System Performance for Tropospheric Communication Circuits with List of References written by and published by . This book was released on 1963 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Equipment Characteristics and Their Relation to System Performance for Tropospheric Communication Circuits written by A. F. Barghausen and published by . This book was released on 1963 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of a tropospheric communications system, either within the line of sight or beyond the line of sight, is directly dependent on the operating characteristics of the equipment. Performance predictions of a communications system are made on the basis that equipment will operate in a prescribed manner. The degree of success of the communications system will depend largely upon how well these predicted values correspond to the actual operating values. Consideration is given to those portions of the equipment that have definite effect upon the operating performance. Specific items of equipment and methods for determining their performance are considered. Representative results in light of the present state of the art permits an evaluation of an actual system in terms of realizing an "optimum" system. In systems that do not have the "optimum" characteristics desired, consideration is given to laboratory devices which may alleviate these deficiencies. Future systems should consider incorporating these devices as development permits.
Download or read book Equipment Characteristics and Their Relation to System Performance for Tropospheric Communication Circuits written by Institute for Telecommunication Sciences and Aeronomy (U.S.) and published by . This book was released on 1963 with total page 820 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by United States. Superintendent of Documents and published by . This book was released on 1963 with total page 792 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supplementary List of Publications of the National Bureau of Standards written by and published by . This book was released on 1960-07 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Use of Measurements in Predicting the Performance of Tropospheric Communication Circuits written by Albrecht P. Barsis and published by . This book was released on 1959 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transmission Loss Predictions for Tropospheric Communication Circuits written by Institute for Telecommunication Sciences and Aeronomy (U.S.) and published by . This book was released on 1967 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book TELECOMMUNICATIONS PERFORMANCE STANDARDS written by Boulder Laboratories (U.S.) and published by . This book was released on 1960 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Predicting the Performance of Long Distance Tropospheric Communication Circuits written by Albrecht P. Barsis and published by . This book was released on 1958 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance Predictions for Single Tropospheric Communication Links and for Several Links in Tandem written by A. P. Barsis and published by . This book was released on 1961 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Performance of long-distance tropospheric communication circuits, either singly or in tandem, is predicted in terms of the probability of obtaining a specified grade of service or better for various percentages of time. The grade of service is determined by the minimum acceptable ratio of hourly median predetection-RMS-signal-to-RMS-noise for the type of intelligence to be transmitted. The standard deviation of prediction errors depends upon the percentage of hours the specified grade of service is required and on parameters characterizing the propagation path. The possibility of reducing this standard deviation by making path-loss measurements is discussed. It is shown that no improvement is possible unless the test path is very nearly the same as the proposed operational path; in particular, unless the test path and operational paths have terminals less than one mile apart it is shown to be doubtful in most cases whether the observations will be useful in improving the reliability of the predicted performance of the proposed system. Assuming that the test path and proposed operational paths are identical, estimates are given of the number of days of observations required to halve the prediction uncertainty or, alternatively, to reduce it to 3 db; in some cases several years of observations are required. A tutorial discussion is given in Appendix III of the concepts of the effective noise figure and the effective input noise temperature of a receiving system.
Download or read book Predicting the Performance of Long Distance Tropospheric Communication Circuits written by A. P. Barsis and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Comparison of calculated and measured values of transmission loss for tropospheric propagation paths shows that there is an appreciable amount of uncertainty in the prediction process. Departures of observed from predicted values may be regarded as normally distributed when expressed in decibels, and this paper considers methods of estimating these standard deviations. In order to predict the performance of a communication system over a given path, it is necessary to define the grade of service, the time availability of this grade of service and the reliability of the predictions. The short-term (within-the-hour) signal fading is conveniently included in the definition of the grade of service, in terms of a required hourly median r.m.s.-carrier to r.m.s.-noise ratio. Next, the time availability of a given grade of service is specified in terms of the percentage of hours in a year that this minimum carrier-to-noise ratio is exceeded. To determine the time availability it is necessary to obtain the distributions with time of hourly medians for the path with given geometrical and meteorological characteristics. In this paper the three concepts, grade of service, time availability, and reliability of prediction are brought together in a single graphical representation. The graph has two probability scales; the ordinate shows the percentage of hours service is available (time availability), and the abscissa shows the service probability (reliability of the prediction), where each curve corresponds to a system with given operating characteristics such as transmitter power, antenna size, etc. Each curve could therefore be labeled by a figure representing installation and operating costs, and various systems may thus be compared on the basis of cost versus probability of successful operation.
Download or read book Naval Shore Electronics Criteria Line of sight Microwave and Tropospheric Scatter Communication Systems written by United States. Naval Electronic Systems Command and published by . This book was released on 1972 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book The Use of Measurements in Predicting the Performance of Tropospheric Communication Circuits written by A. P. Barsis and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The uncertainty in predicting the performance of tropospheric communication circuits may be expressed by a variance, assuming a log-normal distribution of the differences between calculated and measured values of field strength or basic transmission loss, if a number of paths with identical geometrical and other prediction parameters are considered. It is shown to what extent this variance may be reduced by taking into account transmission loss measurements over the same path for which the prediction is intended, or over a similar path. The improved prediction is obtained by assigning weights to calculated and observed values, respectively, and forming a weighted average. The method is demonstrated by examples, and the results are used to calculate new values of service probability on the basis of the improved prediction. Comparison of service probabilities for predictions based on the cal¿̐ư culation above, and for predictions taking into account the results of transmission loss measurements, enables the designer to judge whether the cost of a measurement program is justified in terms of possible savings in equipment for a final installation.
Download or read book European mediterranean Tropospheric Scatter Communication System Performance Specification In band Signaling Equipment written by ITT COMMUNICATION SYSTEMS INC PARAMUS N J. and published by . This book was released on 1962 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: This specification forms a part of Performance Specification ICS-61-SPEC-100, EuropeanMediterranean Tropospheric Scatter Communication System. It covers one type of voice frequency signaling equipment for use in the System which utilizes tone signals transmitted within the limits of the voice frequency channel. (Author).
Download or read book TELECOMMUNICATIONS PERFORMANCE STANDARDS written by Boulder Laboratories (U.S.) and published by . This book was released on 1960 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research Reports written by and published by . This book was released on 1964 with total page 2180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
