Accession Number : AD0893280

Title :   Experimental Cloud Backscatter Measurement at 0.9 Micron.

Descriptive Note : Final rept. Jun-Oct 71,

Corporate Author : MOTOROLA INC SCOTTSDALE AZ GOVERNMENT ELECTRONICS DIV

Personal Author(s) : Brenner, Charles H. ; Gemmell, Frank S.

Report Date : NOV 1971

Pagination or Media Count : 48

Abstract : The performance of a short range optical fuzing system depends, in part, on its ability to reject energy backscattered by atmospheric aerosols. Such a system may be designed whereby the energy received from a true target always exceeds the backscattered energy from an atmospheric aerosol. An aircraft-mounted measurement system was developed for the simultaneous data collection of backscatter energy and one-way path attenuation at short ranges from clouds. Both the one-way path attenuation sensor and the backscatter sensor utilized GaAs laser diodes operating at 0.9 micrometers. The backscatter sensor was a crossed beam ranging device with adjustable range capability. Computer software was developed to process the data recorded during flight tests. Several stripchart recordings are presented which illustrate the relationship of one-way path attenuation and backscatter for cumulus clouds. Over 50 individual cumulus clouds were transited during the flight tests which exhibited visibility ranges as low as 50 ft. (Author)

Descriptors :   (*INFRARED RADIATION, BACKSCATTERING), OPTICAL RADAR, AIRBORNE, ELECTROMAGNETIC FUZES, BACKGROUND, CUMULUS CLOUDS, AEROSOLS, WAVE PROPAGATION, ATTENUATION, RAINDROPS, DENSITY, VISIBILITY, INFRARED DETECTORS, FLIGHT TESTING, SEMICONDUCTOR DIODES, INFRARED LASERS, GALLIUM ARSENIDES, PHOTODIODES, EXPERIMENTAL DATA, DATA PROCESSING, INFRARED RECEIVERS, INFRARED TRANSMITTERS.

Subject Categories : Infrared Detection and Detectors
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE