A Measuring Polygon with a Complex of Polarimetric, Combined Active-Passive Sensors of S-, Ku-, and Ka-band of Frequencies for Soil and Snow Remote Sensing and Surveillance A.K.Hambaryan, A.K.Arakelyan, M.R.Manukyan, and S.A.Darbinyan ECOSERV Remote Observation Centre Co. Ltd. 6 Lazo Str., #31, Yerevan, , ARMENIA Phone: (374 1) / ; Fax: (374 1) s:

Goals To attract attention of researchers engaged in soil, snow and soil vegetation microwave remote sensing activities and, To attract attention of researchers engaged in soil, snow and soil vegetation microwave remote sensing activities and, To interest them to perform their own or joint measurements using available facilities. To interest them to perform their own or joint measurements using available facilities.

The experimental polygon and facilities The complex is dedicated to solve the problem applied to soil and snow moistures retrieval by synergetic application of microwave active-passive means of remote sensing The complex is dedicated to solve the problem applied to soil and snow moistures retrieval by synergetic application of microwave active-passive means of remote sensing Mobile bogie Platform Short pulse scatterometer - radiometer systems

The measuring complex allows carry out polarimetric, multi-frequency, simultaneous and spatially coincident microwave active-passive measurements of observed surface parameters at angles of incidence from the while of 0-60 o The measuring complex allows carry out polarimetric, multi-frequency, simultaneous and spatially coincident microwave active-passive measurements of observed surface parameters at angles of incidence from the while of 0-60 ofrom the while of 0-60 ofrom the while of 0-60 o The experimental polygon and facilities (cont …)

The main technical characteristics of developed microwave devices ParametersRadiometerScatterometer Frequency Band S, K u, and K a Polarization v and h vv; vh; hv; hh Antenna Horn (for K a -band) and parabolic for (S-, and K u -band) antennas Antenna Beam Width 7–15 o in dependence of the band Cross-Polarization Isolation Better than -25 dB Receiver’s Bandwidth ~10 – 20 % ~1-3%

The main technical characteristics of developed microwave devices (cont …) ParameterRadiometerScatterometer Receiver’s Noise Factor 250 – 5000 K ~2 dB Sensitivity at 1s ~0.1 – 0.35 K Absolute Accuracy of Measurements ~2 K ~1.5 dB Radar Pulse Duration ~30 ns Radar Pulse Power ~ mW Weight of Each Sample ~15 kg Power Consumption of Each Sample ~120 W

Microwave modules & antennas of K u and S - band combined scatterometer-radiometers

A block diagram of prototype of S-band, scatterometer-radiometer system Radiometer Output Scatterometer Output Reciever Transmitter

Time Diagram of scatterometer- radiometer operation

Obstacles A necessity in very short pulses creation (~30ns), in reception of the signals reflected from a short distance (~6m); A necessity in very short pulses creation (~30ns), in reception of the signals reflected from a short distance (~6m); A necessity to provide required levels and conditions for decoupling between simultaneously operating radar and radiometer channels of observation of each device, and between radar-radiometer systems of various band of frequencies, operating in very close spatial location. A necessity to provide required levels and conditions for decoupling between simultaneously operating radar and radiometer channels of observation of each device, and between radar-radiometer systems of various band of frequencies, operating in very close spatial location.

Calibration Facilities For absolute measurements of soil, snow and soil vegetation reflective and emissive characteristics an indoor pool of 3.5x5sq.m of size is built in the Polygon; For absolute measurements of soil, snow and soil vegetation reflective and emissive characteristics an indoor pool of 3.5x5sq.m of size is built in the Polygon; The pool water surface may be completely covered, in a few minutes, by a layer of microwave absorber, reflection coefficient of which is better than -25dB for any frequency band, from 1GHz up to 40GHz. The pool water surface may be completely covered, in a few minutes, by a layer of microwave absorber, reflection coefficient of which is better than -25dB for any frequency band, from 1GHz up to 40GHz. This layer is used for external calibration needs of scatterometers and radiometers as an Absolute Black Body. This layer is used for external calibration needs of scatterometers and radiometers as an Absolute Black Body.

Facilities for In-Situ Control-Test Measurments To perform in-situ control-test measurements the experimental Polygon is equipped as well by Pocket Pro 20 Pack – Data Logger System from AquaPro~Sensors (one AP Moisture Probe, one Compaq iPAQ Pocket PC and 20 (1meter) PolyPro Access Tubes); To perform in-situ control-test measurements the experimental Polygon is equipped as well by Pocket Pro 20 Pack – Data Logger System from AquaPro~Sensors (one AP Moisture Probe, one Compaq iPAQ Pocket PC and 20 (1meter) PolyPro Access Tubes); The complex approach to the problem of soil moisture retrieval by synergetic application of data of polarimetric, multi-frequency, combined radar-radiometer observation, attended by in–situ test- control measurements of soil (moisture and temperature), air (temperature), wind (speed and direction) and precipitation (rain and snow volumes and weights, melting time, moisture) parameters, may be successfully solved in this Polygon. The complex approach to the problem of soil moisture retrieval by synergetic application of data of polarimetric, multi-frequency, combined radar-radiometer observation, attended by in–situ test- control measurements of soil (moisture and temperature), air (temperature), wind (speed and direction) and precipitation (rain and snow volumes and weights, melting time, moisture) parameters, may be successfully solved in this Polygon.

Uninterrupted measurements The Polygon hostel and laboratory areas provide opportunity to carry out all-season, all-weather uninterrupted measurements with simultaneous processing of acquired data The Polygon hostel and laboratory areas provide opportunity to carry out all-season, all-weather uninterrupted measurements with simultaneous processing of acquired data

CONCLUSION An experimental Polygon is built, for bare soil, soil vegetation and land snow cover microwave reflective and emissive characteristics simultaneous and spatially coincident measurements; An experimental Polygon is built, for bare soil, soil vegetation and land snow cover microwave reflective and emissive characteristics simultaneous and spatially coincident measurements; The Polygon equipped by: The Polygon equipped by: combined, short pulse S-, K u -, and K a -band scatterometer- radiometer systems, combined, short pulse S-, K u -, and K a -band scatterometer- radiometer systems, facilities for microwave devices absolute calibration, facilities for microwave devices absolute calibration, a set (spatially distributed) for in-situ control measurements of soil moisture and temperature a set (spatially distributed) for in-situ control measurements of soil moisture and temperature facilities for uninterrupted measurements; facilities for uninterrupted measurements; The Polygon may be effectively used for solution of the problems applied to soil and snow moistures precise retrieval by microwave means of remote sensing. The Polygon may be effectively used for solution of the problems applied to soil and snow moistures precise retrieval by microwave means of remote sensing.

Acknowledgements The experimental polygon is a part of the work carried out under the framework of the ISTC (International Science and Technology Center of Moscow) Project A- 872 ; The experimental polygon is a part of the work carried out under the framework of the ISTC (International Science and Technology Center of Moscow) Project A- 872 ; It was built and equipped due to financial maintenance provided by ISTC, as well as by the CRDF (Civilian Research and Development Foundation of the USA) through the Grant NFSAT PH /CRDF awarded by NFSAT (National Foundation of Science and Advance Technologies of Armenia) in the framework of Armenian-US Bilateral Grant Program of the CRDF; It was built and equipped due to financial maintenance provided by ISTC, as well as by the CRDF (Civilian Research and Development Foundation of the USA) through the Grant NFSAT PH /CRDF awarded by NFSAT (National Foundation of Science and Advance Technologies of Armenia) in the framework of Armenian-US Bilateral Grant Program of the CRDF; Authors express their gratitude to both foundations for their maintenance in planned work’s fulfillment. Authors express their gratitude to both foundations for their maintenance in planned work’s fulfillment.

Thank you ! Thank you !

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