А.А. Monakov - Dr.Sc. (Eng.), Professor, Department of Airborne Electronics Equipment, Saint Petersburg State University of Aerospace Instrumentation. E-mail: a_monakov@mail.ru P.I. Ermakov - Post-graduate Student, Department of Airborne Electronics Equipment, Saint Petersburg State University of Aerospace Instrumentation. E-mail: pie13@bk.ru

It is crucially important to compensate the radio wave propagation attenuation for accurate measurements of the precipitation rate and the water content density of atmospheric clouds, as well as for determination of the hazard level of observed meteorological formations for the airtraffic. This compensation can be realized via the statistical estimation of the true reflectivity based on measurements of the received signal power. In the present paper four methods of the true reflectivity estimation are proposed: the nonlinear IIF and FIR fil-ters, the particle filter (PF) and the IMM particle filter (IMM PF). Simulation conducted in the paper shows that all filters have approx-imately the same accuracy, which is close to the accuracy of the statistically efficient estimator. This fact makes the nonlinear IIF and FIR filters more preferable because of their simpler realization. However the model of the true reflectivity distribution within the volume of the simulated meteorological formation, which was used in the paper, is very simple. That is why the final choice can be done only af-ter profound consideration based on experimental data provided not only by radar systems but different meteorological observation tools as well. Analyzed methods of compensation of the propagation attenuation can be also implemented in sonar systems applied in meteor-ology, underwater researches and medicine.

 

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