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It is known that one of the most complicated problem in a radar direction finding is a problem of an effective detection and recognition of objects, especially fixed ones [1,3]. In the paper it is shown that one of the promising approaches for solution of the problem lies in use of polarization parameters of radar-tracking signals.The results of analysis of radiation scattering by objects confirm, that the polarisation characteristics can bear an extensive information both about object parameters and about its operation. It is established, that the polarization characteristics of objects at the specific frequency of exploration and fixed direction of observation can be given by five material parameters (Hujnen's descriptors) [2,4-61:"Noticability or size of an object" (m) -maximum amplitude of a polarized signal is a measure of a size or effective scattering surface (ESS) of object; "Object orientation angle" (cp) -is defined as an angle between a large axe of an ellipse and axe of an object's symmetry (measure of orientation concerning a line-of-sight); " Angle of an ellipticity " ( 7 ) -(measure of object's symmetry to right-hand and left-hand circular polarisation); "Slide angle" (v), describing a multiplicity of signal from object reflections;Polarization angle, characteristic angle " (y), (measure the ability of object to polarize an incident non-polarized radiation).When studying different options of radar-tracking systems construction the specified parameters contain full information about polarization structure of a signal. These parameters are also invariant to object's velocity, power of the reflected signals and polarizing base of the radar-tracking system.In the paper the expressions for calculation of five descriptors are derived and the theoretical investigation on evaluation of possibility of small-size ground objects detection based on polarization properties using polarization parameters vector was carried out.Basic outcomes of experimental research of descriptors for objects in millimeter range are given below which rather well confirm theoretical conclusions about the possibility of such objects detection using polarization parameters vector Fig. 1-3 shows the variants of experimental histograms of m,v and y descriptors approximation for wheel and caterpillar-based (tankemode) vehicles (fixed) and underlying earth surface (equal district with a grass and rare bush of less than Im height) are submitted. The following designations are used: number 1-curve for an light armoured drive truck (EADT), number 2 -for ZIL-131 truck and number 3 -for a underlying earth surface.The experiments shown that the probability of correct detection of objects is 0,87 and 0,81 correspondingly.On the fig. 4 the two-dimensional image for the same objects and similar conditions is given in the space of parameters z and m. Here z is magnitude of a ratio component cross-sectional and basic polarizations expressed in decibels. The A numeral designates magnitude z for a underlying earth surface, 0-the same for ZIL-131 and...

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