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This report reviews antenna configurations for use on an ocean data buoy platform. Both electrical and mechanical requirements are con­sidered. A sleeve dipole antenna appears most suitable for small buoys. For large buoys. a discone antenna should b...

The effects of multipath arising when a signal transmitted from a User satellite is scattered by the earth before reaching a tracking and delay relay satellite (TRDS) in stationary orbit are considered. An upper bound for the probability of the scatt...

A numerical method for calculating the scattering and diffraction at an antenna site to be used in a sky-wave communication link is derived. The method of physical optics is used to treat the scattering by the terrain surrounding the antenna site. ...

An estimate of the existing HF electromagnetic interference environ­ment was made for the U. S. Navy receiving antenna area in Bremerhaven, Germany. The estimate was based on land use in the area and measure­ments of man-made radio noise from various...

An algorithm is presented which permits calculation of the transmitter power required to achieve a given value of circuit reliability or service probability and time availability on high-frequency ionospheric tele­communication systems. The accuracy ...

Continuous wave signals at 9. 6 GHz were propagated over a 97 -KM overwater path extending from 80 m to 3000 IT) above mean sea level. Variations in phase of arrival of the signals received by antennas having 1. 2 and 5* beam widths were recorded sim...

The results of three research projects for the period January 1968 through December 1968 are reviewed. The first was to develop a program (ALLMODES) that presents circuit data for the 7 most probable ionospheric sky-wave transmission modes. The secon...

This memorandum describes FORTRAN routines for printer-plotting distribution functions on a normally scaled graph. Included are related routines for handling distribution functions.

Based on trends of recent ionospheric and solar data, the IPR series of Semimonthly Revision Factors for ITS Ionospheric Predictions provides corrections to the monthly ITS Ionospheric Predictions for F2-layer MUF. Accuracy of the IPR revision factor...

An evaluation of three refractivity variables in terms of their value in correcting microwave slant-range data for atmospheric effects is described. Experiments were conducted in Hawaii in 1967 on a fixed, 65 km overwater propagation path. The data o...

A hypothetical aircraft-to-ground communication channel is examined for frequencies in the 2 -30 MHz band, and in the 200 -400 band. The channel is characterized by its correlation function and scatter function. Particular attention is given to the e...

An investigation of radar microwave relay outages resulting from excessive fading on the line-of-sight microwave relay system indicated that most were caused by multipath propagation which resulted in phase interference fading. Rain attenuation was a...

The ESSA/ITS HF system performance prediction program has been modified and adapted to operate on a time-share computer. The problems and solutions of implementation are discussed. A description is given of the routines used in the prediction program...

This report describes an experiment in which some computations are compared with available field strength data. Several models are proposed which compute an effective height by using a least squares fit to various sections of the terrain profile. Als...

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...