Search Results
The search returned 1,243 publication(s) on its.ntia.gov.
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...
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...
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. S...
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...
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...
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...
Several approximations to the attenuation coefficient caused by double knife-edge diffraction are given in terms of the single knife-edge attenuation coefficient. These approximations are evaluated for several typical double knife-edge paths and com...
To assist NAV/SEEC in the evaluation of locations for a NAVCOM receiving site, the Electromagnetic Interference Environment Program Area personnel conducted a field measurement and analysis program. Interference levels from base supported, man-made n...
Most people know that radio, television, long distance telephone, radar, police radio, etc., play important roles in their daily lives. Hany of the more thoughtful are aware that telecommunication services are important, indeed essential, participan...
This report by the Director of Telecommunications Management on Frequency Management within the Executive Branch of the Government contains an appeal for immediate implementation of a major planning program for the future allocation and use of the r...
Vertical radiation patterns of vertical quarter-wave monopoles, and of vertical and horizontal half-wave dipoles located at various heights up to twenty wavelengths over several typical types of ground are shown. Vertical antennas have the best low-...
The theoretical on-axis gains of 134 terminated rhombic antennas are calculated for vertical radiation angles from 0 degrees to 45 degrees.
The characteristics of oblique sounding and backscatter sounding are discussed. The requirements imposed upon antennas for either form of sounding are considered. The available antenna types are reviewed from the standpoint of their suitability for...
This report documents a FORTRAN program which computes the electric field components due to vertical electric or magnetic dipoles. The ground constants and antenna heights are arbitrary. Sample calculations and an annotated listing are included.
A description of several investigations concerning high frequency backscatter is presented. These deal with travelling ionospheric irregularities, topside sounder-bottomside backscatter sounder comparisons, backscatter Doppler observations, ray trac...
Maps and charts are presented giving the world wide distribution and relative occurrence of ducting and superrefractive gradients of the radio refractive index for the atmospheric layer nearest to the surface. Areas with frequent occurrences of duct...
Geographic and frequency dependent distributions of atmospheric noise power enumerated in CCIR Report 322 [1964] are approximated by series expansions for use in electronic computers. Coefficients of Fourier series representation of worldwide geograp...
The various causes of fading and the various kinds of diversity are described. Detailed design procedures are given for the two most popular diversity systems, a redundant technique in which two channels at different frequencies are used and a non-r...
The problem of point-to-point radio communication on the moon is discussed, and equations and curves are presented to estimate power requirements in lunar communication systems. Assuming a smooth surface, consideration is given to ground wave attenu...
A collection of titles and abstracts is presented for articles dealing with the microwave fading that has been observed on tropospheric line of sight paths. Selections are included for related subjects such as: measurement of meteorological factors;...