A.V. Boldin, R.P. Bistrov, U.I. Mamon, A.A. Potapov, V.L. Rumyantcev
For investigation of non-linear objects reflecting features experimental – investigative complex is proposed, allowing to carry out the measurements of electromagnetic field scattering characteristics on the second and the third harmonics of sensing frequency. Half-wave antenna, airport ladder, motor vehicle UAZ, scrap metal (building structures, metal components) were used as radar objects with non-linear features. As a result of conducted investigation the dependencies of voltage in the receiver out-put upon target range were gained.
It is shown, that experimentally obtained stress relationships of the receiver field have intraditional character in the function of range, whereas approximation by two curves is needed. The presence of different laws coupling stress values of received field (in the range of “weak” and “strong” signal) on receiving reflected wave on n-th harmonic testifies the change of non-linear absolute cross-section dedending on electromagnetic wave power flow incident to the object.
The magnitude of non-linear absolute cross-section of radar objects, used in experiment during receive of reflected signal on the third and the second harmonics is defined. The ratio for received signal energy in the output of receiving antenna in the case of radars continuous radiation is derived. It is defermined that in the absence of background returns radar objects are detected better by classical radiolocation methods. However, in the presence of background returns the use of radar targets non-linear properties allows to increase their detection range. The results may be used during evaluation of non-linear objects detection capabilities.