Search Results

The search returned 1,237 publication(s) on its.ntia.gov.

Harold T. Dougherty, “Microwave Fading with Airborne Terminals,” Technical Report IER 58 ITSA 55, October 1967

After a brief description of the significance of the radio refractive index and its variation in the atmosphere, a brief catalogue of fading mechanisms is presented. Attention is directed to the variety of fading mechanisms that are pertinent for th...

M. E. Johnson, Martin J. Miles, Paul L. McQuate, and Albrecht P. Barsis, “Tabulations of VHF Propagation Data Obtained Over Irregular Terrain at 20, 50, and 100 MHz Part 2: Colorado Mountain Data,” Technical Report IER 38-ITSA 38-2, August 1967

This report contains tabulations of transmission loss data resulting from propagation experiments at 20, 50, and 100 MHz conducted over irregular terrain in the Colorado Mountains primarily east of the Continental Divide. Raw data from measurements ...

Margo Leftin, Sidney Maurice Ostrow, and C. Preston, “Numerical maps of monthly median h’F, F2 for solar cycle minimum and maximum,” Technical Memorandum IER TM ITSA 69, July 1967

Numerical maps of h IF, F2 were prepared for all 12 months of 1954, a solar cycle minimum year, and of 1958, a solar cycle maximum year. To fill major gaps in the world coverage of observed data for these years, we used some supplementary data observ...

Jean E. Adams, “Measurements of the Performance of Two HF log Periodic Antennas at the Lincoln Receiving Site of McClellan AFB,” Technical Memorandum IER TM ITSA 94, June 1967

Antenna performance measurements were made on five HF antennas to determine their acceptance as prototype antennas for the Air Force HF communication circuits. The impedances. power gain, and radiation patterns of two of the log periodic antennas are...

Laurance G. Hause and C. F. Peterson, “Passive reflector measurements at 9.2 and 4.6 GHz,” Technical Memorandum IER TM ITSA 64, June 1967

1. Path loss median values can be substantially greater than one might expect from simple line-of-sight calculations especially where one leg of the path is very long. 2. Small passive reflectors have application at frequencies considerably below 4 ...

C. F. Peterson, Charles A. Samson, Joseph E. Farrow, and Evelyn M. Gray, “Radio and Meteorological Observations on an obstacle diffraction communication link in Europe, Radio and Meteorological Observations on the 11. 1 -46 Radio Link of the ET-A System,” Technical Memorandum IER TM ITSA 65, June 1967

An investigation of the performance of a 405 km obstacle-diffraction radio link between Germany and Italy was made during June and July 1966 to evaluate contributions of both the antenna system and local meteorological conditions to propagation outa...

M. E. Johnson, Martin J. Miles, Paul L. McQuate, and Albrecht P. Barsis, “Tabulations of VHF Propagation Data Obtained Over Irregular Terrain at 20, 50, and 100 MHz,” Technical Report IER 38-ITSA 38, May 1967

This report contains tabulations of transmission loss data resulting from propagation experiments at 20, 50, and 100 MHz conducted over irregular terrain in the Colorado high plains east of the Continental Divide. Raw data from measurements describe...

Herman V. Cottony, “Measurement of antenna radiation efficiencies,” Technical Memorandum IER TM ITSA, May 1967

The definition of radiation efficiency is stated and the principles and practice s in measuring it are reviewed. Particular attention is given to the rhombic antenna because of its practical importance at HF and because its efficiency can be determin...

James R. Wait and Eileen A. Brackett, “Bibliography on Waves in Plasmas,” Bibliography IER 39-ITSA 39, April 1967

Bibliography on Waves in Plasmas

James C. Blair, “Monitoring techniques for evaluating useful frequencies for HF telecommunication circuits,” Technical Memorandum IER TM ITSA, March 1967

Significant channel characteristics of HF communication circuits are reviewed, with particular emphasis on their importance in the evaluation and selection of useful operating frequencies. Various theoretical and experimental results from several sou...

R. Marshall Coon and W. D. Bensema, “Instrumentation and analysis technique for the measurement of HF channel characteristics,” Technical Memorandum IER TM ITSA 11, March 1967

This report describes a means of measuring and analyzing the transfer characteristic of an HF channel in terms of the effects of the medium on 229 closely spaced sinusoids. The method involves transmission, reception, measurement, and computer analys...

Robert T. Disney, Arthur D. Spaulding, William Q. Crichlow, and R. C. Davis, “Minuteman Radio Launch Control System Studies and Site Survey,” Technical Memorandum IER TM ITSA 32, March 1967

To evaluate the performance of the Minuteman Radio Launch Control System, a number of factors were investigated. This report gives the results of the field measurement programs conducted by ITSA. In addition to the radio noise evaluation, measurement...

G. D. Gierhart and M. E. Johnson, “Interference Predictions for VHF/UHF Navigation Aids,” Technical Report IER 26-ITSA 26, March 1967

Desired-to-undesired signal ratio predictions for the VHF Omnirange (VOR), Tactical Air Navigation (TACAN) and Instrument Landing Systems (ILS) air navigation aids are presented in this report. The parameters involved in the various systems are given...

Douglass D. Crombie and James M. Watts, “Observations of coherent backscattering of hectometric radiowaves from along the sea surface,” Technical Memorandum IER TM ITSA, February 1967

Observations of coherent backscatter from the surface of the sea, at range s up to 200 km, using a slightly modified ionosonde are described. The range of frequencies used was between 2.6 and 8.5 MHz corresponding to sea wave lengths of 58 -17m and ...

Leslie A. Berry, “Radio Propagation over a Gaussian Shaped Hill,” Technical Memorandum IER TM ITSA 41, February 1967

The propagation factor for wave propagation over an impedance surface containing irregularities large compared to a wavelength is the solution of a certain integral equation. The equation is solved numerically for the special case of a two-dimension...

P. L. Rice, A. G. Longley, K. A. Norton, and A. P. Barsis, “Transmission Loss Predictions for Tropospheric Communication Circuits: Volumes I and II,” Technical Note TN-101 Vols. I and II, January 1967

This report presents comprehensive methods of calculation which have been found useful either for explaining or for predicting cumulative distributions of transmission loss for a wide range of radio frequencies over almost any type of terrain and in...

G. D. Gierhart, “Frequency sharing with air traffic control satellites,” Technical Memorandum IERTM-ITSA-26, January 1967

Technical information relevant to the solution of frequency sharing problems in the VHF band that are associated with the use of VHF for the aircraft/ satellite link of a synchronous satellite air traffic control system is included in this report. Sp...

George W. Haydon, “Theoretical evaluation of band 7 frequency complements for ocean data communications,” Technical Memorandum IER TM ITSA 54, January 1967

A study has been conducted to evaluate selected complements of Band 7 frequencies (3-30 MHz) by the application of radio propagation data to a hypothetical deployment of ocean buoys about base stations in various geographic areas. The relative utilit...

Donald R. Macken, C. L. Harbison, and John J. Tary, “A tele­communications study for the National Crime Information Center,,” Technical Memorandum TM ITSA 30, January 1967

The National Crime Information Center consists of a real time data acquisition and storage system plus an extensive telecommunications network to permit law enforcement agencies throughout the United States to enter data and to interrogate the system...

John S. Nicolis and Carolen Moncure, “Calculation of electrical length variations and focusing-defocusing due to tropospheric layers in microwave propagation,” Technical Memorandum IER TM ITSA 39, January 1967

Numerical results concerning the disturbances caused by a typical category of slightly subrefractive or superrefractive thick tropospheric layers in line-of-sight propagation as well as the importance of total reflection from such layers. These refle...