Search Results
The search returned 1,243 publication(s) on its.ntia.gov.
This report is a system description and performance evaluation of a two-way system for communicating between a shore station and one or more ocean buoys or ships. The probabilities of various errors of omission and commission are considered. It is co...
This manual describes services provided by the Telecommunication Services Center to support operation of high-frequency ionospheric communications systems. The communicator obtains services he requires by a TTY terminal in his facility. Use of a dedi...
Atmospheric radio-noise samples were recorded near Boulder, Colorado, and analyzed to obtain amplitude and time statistics of MF and HF noise. Amplitude and time statistics derived from the Hall model were compared with the corresponding measured st...
A theoretical study of the radio frequency interference (RFI) environment has been performed for an existing communication complex that uses VHF, UHF, and microwave communication equipment and is located On top of Capitol Peak in the State of Washing...
Supported by data taken over a 65-km. slant path with fixed terminals, this report suggests exploitation of the dispersion between radio and optical signals for studying the atmospheric errors in radio range measurements over propagation paths with a...
The line shape of the self-broadened rotational (5−1 → 6−5) transition of water vapor at v 0 = 22.235 GHz has been investigated on the basis of resonance dispersion information. Detailed information on absolute intensity, width, shift, and wing respo...
This is the second part of a four-part report containing tabulations and graphs of transmission loss data resulting from propagation experiments in the 230 to 9200 MHz frequency range conducted over irregular terrain in Colorado. This part describes...
Near-zone field strengths are calculated both on axis and on a grid behind the high power electronically steerable HF radar array to be erected near Platteville, Colorado. These calculations and measurements of the shielding effectiveness of the buil...
Three FORTRAN computer programs for generating spherical Bessel functions are described. A brief discussion of the method of calculation and the capabilities of the programs is followed by a detailed "users manual". The program listings are included ...
Propagation measurements were made at 6. 8 GHz during August 1967 over a 65-km. line-of-sight path in Ohio. During three periods of severe fading, both space and frequency diversity provided marked improvement over nondiversity operation. Comparisons...
A method of high precision arithmetic has been devised for the CDC-3800 computer based on nonstandard type. The precision extends up to 324 bits for normal arithmetic operations, and up to approximately 310 bits for exponentiation.
This report describes a computer method for predicting long-term median transmission loss over irregular terrain. The method is applicable for radio frequencies above 20 MHz and may be used either with detailed terrain profiles for actual paths or w...
Two charges of TNT, each 100,000 Ib in size and hemispherical in shape, were detonated at ground level on the White Sands Missile Range, New Mexico. One function of the experiment was to measure the propagation and spectral characteristics of the aco...
The radiation patterns and power gains of two HF corner reflector array antennas--a two-element corner-reflector array antenna rotatable in azimuth and operating from 10 to 27 MHz, and a 20-element corner-reflector array antenna mechanically fixed ...
This report presents the results of laboratory tests conducted to make preliminary determination of the required protection ratios for satisfactory sharing service in a VHF ATC communications system. The data given may be used to predict a quantitati...
This four-part report contains tabulations and graphs of transmission loss data resulting from propagation experiments in the 230 to 9200 MHz range conducted over irregular terrain in Colorado. Each part of the report deals with data obtained at a s...
After a brief description of the significance of the radio refractive index and its variation in the lower troposphere, a catalog of fading mechanisms is presented. Attention is directed to the supporting refractive index structure, the characteristi...
This report is a supplement to ESSA Tech. Report IER 54-ITSA 52 by the same authors. Two additional models of log-periodic dipole arrays over several types of ground are studied in the present work. The total field above the ground is computed and p...
In this report is described a highly flexible digital data acquisitions system that can be duplicated for $8,000. The system is for VLF research, but it could be easily adapted to a wide variety of problems. It is capable of sampling up to 16 channel...
Observations of 9.2, 11. 2, 12.2, 13.6, 15.2, and 17.2 kHz Omega signals radiated from Forestport, New York, and from Haiku, Hawaii, as received at Boulder, Colo., and at Anchorage, Alaska, are presented. Phase and amplitude data collected at these f...