rization (wavelength). The decision function R here can he
determined in the general case as
R-R(A%(P,),a%(Pj) ■■■aT(p„)) , (4)
where P^, ... P^ are polarizations
A Zi? = z\ 7) + & ( ¿a T#)
Until recently, practical use has mainly been made of
the measurements on two orthogonal and circular polariza
tions. For most plants on the horizontal polarization ab
sorption is much less than on any other and, thus, this
polarization is optimum when applied to the solution of the
problem of detection of the boundary ”land-water” under the
vegetation layer. Shown in Fig. 1 is the fragment of the
registergram with synchronous recording of the radio-ther
mal signal showing that the boundary ”land-water” is cha
racterized by a sharp decrease in the radio-brightness
temperature. Thus, in the case of microwave radiometrical
sensing the refining of the boundary poses no difficulty.
The problem of discrimination of boggy sections of
the terrain is similar to the problem considered above,
but it is distinguished with a number of specific features
in selection of the criterion against the value of which
the decision is taken on the presence or absence of boggy
areas. The registergram of the radio-thermal signal cor
responding to the route passed through the boggy terrain
