Voice Communication Via Scattered Ultraviolet Radiation. Volume 1

Abstract : Nonline of sight voice communication has been accomplished in broad daylight via atmospheric scattering of ultraviolet radiation in the solar blind region of the spectrum. A frequency modulated high repetition rate hydrogenxenon flashlamp is used for the transmitter and a combination of solar blind filters and photomultiplier tube is used for the receiver. An analysis is presented to show the potential for a practical, short range, all weather, secure, jam resistant communications system. An experimental study has been performed to systematically determine the scattering and absorption characteristics of ultraviolet light in the lower atmosphere, in both clear and rainy weather. A simplified atmospheric scattering theory has been developed which shows excellent agreement with the observed data. The theory utilizes the generalized Henyey-Greenstein phase function modified to resemble Deirmenjian's phase functions for polydispersed aerosols.