Accession Number : ADA194504

Title :   Rain Attenuation at 35 GHz Over an 18-KM Path.

Descriptive Note : Rept. for Jun 85-Dec 87,

Corporate Author : ROME AIR DEVELOPMENT CENTER GRIFFISS AFB NY

Personal Author(s) : Altshuler, Edward E

PDF Url : ADA194504

Report Date : Mar 1988

Pagination or Media Count : 29

Abstract : In this paper an experiment to measure attenuation as a function of rain rate is described. The measurements were made at a frequency of 35 GHz over an 18.3-km path between Griffis Air Force Base and Verona, NY. Four tipping-bucket rain gauges were located along the path. The beamwidths of the antennas were sufficiently narrow and the antennas were sufficiently high above the ground so as to preclude interference from any terrain effects. Rain rate and received signal level were measured at one-minute intervals; however, equipment malfunctions prevented data from being collected on a continual basis. In addition, it was found that the rain gauges did not operate reliably during snow and very cold weather so they were not used during the winter. Therefore, it was not possible to obtain percent time statistics for rain attenuation for upper New York State. However, 91.5 hours of data were collected during 10 rainstorms. A linear regression of attenuation as a function of rain rate was performed for each set of data. Based on the results that were obtained it appears that the rain attenuation has a fair amount of variability and that the measured attenuations are somewhat higher than those predicted by theory. A reason for this excess attenuation may be due to the fact that the rain gauges were spread too sparsely along the path and that heavier localized rain went undetected.

Descriptors :   *ATTENUATION, *RAIN, *RAINFALL INTENSITY, AIR FORCE FACILITIES, ANTENNAS, COLD WEATHER, LINEAR REGRESSION ANALYSIS, MALFUNCTIONS, NEW YORK, RAIN GAGES, RATES, SIGNALS, SNOW, STATISTICS, TERRAIN, TIME, WINTER

Subject Categories : Meteorology
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE