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In this paper the results of polarization measurements of clear air and clouds brightness temperatures at 37GHz are presented. The results were obtained during the measurements carried out in Armenia from the measuring complex built under the framework of ISTC Projects A-872 and A-1524. The measurements were carried out at vertical and horizontal polarizations, under various angles of sensing by Ka-band combined scatterometric-radiometric system (ArtAr-37) developed and built by ECOSERV Remote Observation Centre Co.Ltd. under the framework of the above Projects. In the paper structural and operational features of the utilized system and the whole measuring complex will be considered and discussed as well.

In this paper the results of simultaneous and spatially coincident, multi-frequency, polarimetric, spatio-temporally collocated measurements of waved pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at 5.6GHz, 15GHz and 37GHz are presented. Angular measurements were carried out for various water surface roughness parameters at clear air, cloudy and rain conditions. For these measurements C-, Ku and Ka-band, polarimetric, combined scatterometric-radiometric systems were used, set jointly on a mobile buggy moving along the measuring platform. Structures, operational features and the main technical characteristics of the utilized systems are presented too. The paper has an aim as well to attract attention of interested researchers and to invite them to perform their own or joint researches using available devices and facilities.

In this paper the results of spatio-temporally collocated polarization measurements of snow and bare soil (covered by old and dry lying stems of wheat and weed) microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at ~37GHz are presented. As well as a structure and operational features of utilized Ka-band, multi-polarization, combined scatterometer-radiometer system, measuring and calibration facilities are discussed.

In this paper a dual frequency (at C- and K u -band), multi-polarization, combined, short pulse scatterometer-radiometer system is described. The developed system is applicable for simultaneous and spatially coincident, dual-frequency and multi-polarization measurements of soil, snow and water surface microwave reflective and emissive characteristics from a range beginning of 4m.y

In this paper the results of simultaneous and spatially coincident, multi-frequency, polarimetric, spatio-temporally collocated measurements of waved pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at 5.6GHz and 15GHz will be represented. Angular measurements were carried out for various water surface roughness parameters at clear air, cloudy and rain conditions. For these measurements C-, and Ku-band, polarimetric, combined scatterometric-radiometric systems were used, set jointly on a mobile buggy moving along the measuring platform. Structures, operational features and the main technical characteristics of the utilized systems are presented too. The paper has an aim as well to attract attention of interested researchers and to invite them to perform their own or joint researches using available devices and facilities.

In this paper the structure and operational features of Ka-band, combined scatterometric-radiometric system and the results of spatio-temporally collocated measurements of perturbed pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at ~37GHz are presented, curried out under clear air, heavy clouds and rain conditions.

In this paper the structure and operational peculiarities of reconstructed, Ka-band, combined scatterometer-radiometer system are discussed. The developed system is suitable for spatio-temporally collocated, high precise measurements of the absolute values of water surface, snow, bare and vegetated soils microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics at ~37GHz, under test-control laboratory conditions from low altitude measuring platforms.

In this paper the structure and operational features of C-band, multi-polarization, combined scatterometer-radiometer system and the results of preliminary, spatio-temporally collocated measurements of waved pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at ~5.6GHz are presented.

In this paper the structure and operational features of Ku-band, multi-polarization, combined scatterometer-radiometer system and the results of preliminary, spatio-temporally collocated measurements of bare soil and waved pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at ~15GHz are presented.

In this paper the structure and operational features of C-band, multi-polarization, combined scatterometer-radiometer system and the results of preliminary, spatio-temporally collocated measurements of bare soil and land snow cover microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at ~5.6GHz are presented. Keywords: Radar, radiometer, radar backscattering coefficient, radio brightness temperature, soil and snow moistures, soil temperature, snow temperature. 1. INTRODUCTION The results of various experimental and theoretical researches applied to the Earth surface (sea, land) and atmospheric microwave remote sensing have shown that multi-parameter dependence of the observed surface radar backscattering coefficient and brightness temperature is the main obstacle to achieve unambiguous and precise solution for inverse problems of the earth remote sensing. In particular, soil and snow microwave reflective and emissive characteristics (radar backscattering coefficients and brightness temperatures) are complex functions of the following principal parameters: soil and snow moistures, soil and snow temperat ures, soil type, snow depth, soil and snow structures, soil and snow salinities, soil vegetation characteristics, snow melti ng time, etc. [1-9]. For unambiguous and precise retrieval of a specified parameter, such as soil or snow moisture, snow depth and melting time, soil salinity, ice salinity, snow or soil temperature, near surface air temperature and wind field parameters, etc., it is necessary to have a priori information about other influenced parameters or to synergy various independent and differing techniques and data of measurements. Spatio-temporally combined multi-polarization, active-passive measurements of bare and vegetated soil and snow parameters are examples of such a synergy. For precise and unambiguous solution of land surface (soil, vegetation, snow, ice) microwave remote sensing inverse problems it is n ecessary as well to improve radiative transfer models of the observed surfaces. For this purpose it is necessary and very significant to develop and to manufacture combined radar-radiometers, suitable for short range remote sensing, which will allow perform field or quas i-field measurements under test-control laboratory conditions. Such a task was solved in Armenia by ECOSERV Remote Observation Centre Co. Ltd. [10-15] in the framework of the ISTC (International Sc ience and Technology Center) Project A-872, which had the aim to develop and to build an experimental site equipped by a measuring complex of L-Ka band combined, short pulse scatterometer-radiometer systems for short distance application (at ~5m minimum operational range for scatterometers). The objectives of the above mentioned Project were successfully achieved and S (~3GHz), K (~20GHz) and Ka (~37GHz) band, single-polarization, combined, short pulse s catterometer-radiometer systems were developed and tested in the field conditions by ECOSERV Remote Observation Cent re Co. Ltd. [10-15]. Further activities in the framework of the Projects FSMP ARG2-5041-YE-04, NSMP ARG2-579-YE-04 and GAP ARG2-1685-YE-04 of the US Civilian Research and Development Foundation were successfully accomplished by a development of C- and Ku-band, dual polarization, dual channel, combined short-pulse scatterometer-radiometer systems. In this paper a C-band (~5.6GHz), dual polarization, dual channel, combined short-pulse scatterometer-radiometer system is described, for short , middle and long distance remote sensing app lications (from 5m to 2500m) from airborne

In this paper a measuring complex of C-, Ku and Ka-band, multi-polarization, combined scatterometer-radiometer systems, their structures and operational features, measuring platforms and calibration facilities are presented. As well as the results of preliminary, spatio-temporally collocated, multi-frequency and multi-polarization measurements of waved pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at 5,6GHz and 15GHz are presented.

In this paper a measuring complex of C-, K u and K a -band, multi-polarization, combined scatterometer-radiometer systems, their structures and operational features, measuring platforms and calibration facilities are presented. As well as the results of preliminary, spatio-temporally collocated, multi-frequency and multi-polarization measurements of bare soil microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at 5,6GHz and 15GHz are presented, under various soil moisture and air temperature conditions.

In this paper a C-band (~5.6GHz), double channel, polarimetric, combined short-pulse scatterometer-radiometer system is described. The system was developed for short distance remote sensing application (from 6m up to 100m), from stationary fixed platforms or vessels. The minimum operational range for the scatterometer is 6m. This capacity allows study correlative features between microwave reflective and emission characteristics of the observed surfaces and medium under control-test laboratory conditions. Although the system was developed for polarimetric (vv, vh, hh, hv), simultaneous and spatially coincident microwave active-passive measurements of water surface, bare and vegetated soils and land snow cover parameters, it may be successfully used for atmospheric boundary layer remote survey too.

In this paper a Ku-band (15GHz), dual polarization, combined short-pulse scatterometer-radiometer is developed for short distance remote sensing of the water surface, bare soil and snow cover, as well as for simultaneous and coincident measurements of the microwave reflective and emissive characteristics of the observed medium under laboratorycontrolled conditions. The system allows us carry out polarimetric (vv, vh, hh, hv), simultaneous and coincident microwave active-passive measurements of the observed surface (soil, vegetation, snow and water surface) parameters at angles of incidence from 0-60°. The originality of the developed system is in the spatial-temporal combination of microwave active and passive channels of observation and its application for short distance sensing (the minimum operational range for the scatterometer is ~6m) from low altitude platforms under far field conditions for both radar and radiometric observations.

In this paper preliminary results of simultaneous and spatially coincident measurements of water surface, bare and vegetated soil and snow microwave reflective and emission characteristics at 37GHz is represented. The measurements were carried out by combined radar-radiometer system of Ka-band (~37GHz) of frequency set on a stationary platform of 6.5m of altitude.

S-band, be-polarization, combined, short pulse (~25ns) scatterometer-radiometer system is described, for water surface, bare soil, land snow and vegetation covers short range (~5m) remote sensing.

A complex of polarimetric (dual polarization), spatio-temporally combined active-passive devices of S (~3GHz), C (~5.6GHz), Ku (~20GHz), and Ka (~37GHz) band of frequencies is represented, for bare and vegetated soils, waved water surface and land snow cover microwave reflective and emissive characteristics simultaneous, multi-frequency, polarimetric and spatially coincident measurements. The complex is dedicated to solve problems applied to soil (bear and vegetated) and snow moistures retrieval, to near water surface wind and wave field parameters retrieval, by microwave means of remote sensing, as well as applied to surface and sub-surface targets detection and identification tasks solution. The complex is set in ECOSERV ROC's control-test experimental site, in Armenia, which is equipped by facilities for microwave devices absolute calibration, by spatially distributed stations for in-situ measurements of soil moisture and temperature, and has a local meaning small weather station. This paper has an aim to attract attention of researchers who are interested in such kind measurements and to invite them to perform their own or joint measurements using available facilities.

A concept of combining data of altimeter and slight tilted radiometer observations and a microwave active-passive, combined method of detection and identification of sea surface signatures are presented. Developed method allows detect the sea surface microwave slight-contrast signatures and identify precisely the origins of their formation.

In this paper C-band (~5.75GHz), dual polarization, Doppler scatterometer is developed, for short distance remote sensing of water surface microwave reflective and spectrum characteristics simultaneous and coincident measurements, under laboratory-control conditions. Developed system will be set on a mobile bogie moving on the height of 6.5m along a stationary platform of 32m of length. It will allow carry out polarimetric (vv, vh, hh, hv), simultaneous and coincident microwave active measurements of pool water surface parameters at angles of incidence from the while of 0-40o.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper Ka-band (37GHz), dual polarization, combined short-pulse scatterometer-radiometer is described, for short distance remote sensing of bare soil and land snow cover and for simultaneous and coincident measurements of observed media microwave reflective and emissive characteristics, under laboratory-control conditions. Developed system is set on a mobile bogie moving on the height of 6.5m along a stationary platform of 26m of length. It allows carry out polarimetric (vv, vh, hh, hv), simultaneous and coincident microwave active-passive measurements of observed surface (soil, soil vegetation, snow and water surface) parameters at angles of incidence from the while of 0-60o.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.