EXPERIMENTAL RESEARCH OF RADIO THERMAL contrasts of the OBJECT IN THE MILLIMETer
L. I. Fedoseev, R. P. Bystrov,
I. V. Kuznetsov, J. V. Lebsky, V. A. Maltsev, A. A. Shvetsov, A. P. Shkaev, A.
Applied Physics Institute of RAS, Nizhniy Novgorod
Received December 13, 2010
The summary results the
hardware-methodical workings out and measurements radio-thermal contrasts of
district and objects on its background in a millimeter range of lengths of waves
are given. Questions of formation, ordering and forecasting of radio thermal
contrasts are mentioned.
The supervision begun still in 40th
years own ÑÂ×
radiations of atmosphere of the Earth have been spent for the first time in 1946
by Daik. Detailed researches of selective radiations of atmospheric components
are executed by V.S.Troitskiy, S.A.Zhevakin. In 50th years successful
development of a range of millimeter waves were continued, and soon it has led
to creation of unique sources of radiation - backward-wave tube,
high-sensitivity not cooled radio astronomical reception equipment,
high-precision mirrors etc. on waves up to 1 mm. Later works by electrodynamics
and statistical calculations of spectral and spatial characteristics of radio
thermal radiation of gaseous environments and the environments, which are
limited by smooth surfaces. Representations about mechanisms of
fluctuation of intensity radio-thermal radiations are developed. Measurement
techniques for millimeter wave
radiation is developed taking into account the requirements of scientific and
applied researches. Use of all of it has allowed to receive an extensive data
set on atmospheric absorption and radiation. There was naturally a
question about the application of all listed above in applied researches,
in particular. The first works in this area were directed to the data
acquisition for the estimation of degree of a marketability of possible
applications of radio
thermal systems in the
conditions of unusually big absorption (from the points of view of that time).
The following works have been directed on revealing the relation between the
main radiometric characteristics of the object: it's brightness contrast
with the background and atmosphere characteristics, strongly depending in
millimeter wave range upon meteorological conditions, a season and a
relief. The establishment of such relation would allow to solve a problem of
forecasting of contrasts in various regions with various environmental
conditions, and then of a maximum efficiency in them of any radio-thermal
systems, having optimized thus their working frequencies and other parameters.
Importance of such approach to researches is not lost now. Results of
hardware-methodical workings out and the natural researches executed by group of
employees in Applied
Physics Institute of
the Russian Academy of Sciences.
radio thermal contrast,
millimeter waves, own radiation, receiving equipment, fluctuation, atmosphere,
radio thermal background, radiometer.