RADIOLOCATION METHOD OF DETECTING ANOMALIES OF GIVEN CLASS Russian patent published in 1994 - IPC

FIELD: method of detection. SUBSTANCE: method concludes irradiation of part of surface to be tested, reception of reflected signal, reception of radio-thermal signal irradiated by part under test and correlation treatment of signals; reflected signal and irradiated radio-thermal signal are received simultaneously. Received reflected signal is additionally squared. Then reflected received signal is accumulated and multiplied by the first weight coefficient. Radio-thermal signal is squared, accumulated and multiplied by the second weight coefficient. Received reflected signal is multiplied by irradiation signal. Total signal is filtrated and the first quadrature component of reflected signal is selected. Then the received reflected signal is re-multiplied by radiation signal which is phase shifted for 90 deg.. Total signal is filtrated and the second quadrature component of reflected signal is selected. Resulting signal is formed due to division of the second quadrature component by the first quadrature component. Result of division is differentiated and differentiated signal is multiplied by signal, achieved in form of relation of square of the first quadrature component to sum of squares of the first and the second quadrature components, when the value of the first quadrature component is not equal to zero. The resulting signal is formed which is equal to zero at zero value of the first quadrature component of reflected signal. The resulting signal is squared, accumulated. Accumulated resulting signal is squared. The first additional signal is formed by subtraction from accumulated squared resulting signal. The squared accumulated signal is multiplied by the third weight coefficient of additional signal and then is compared with threshold value. In this case weight coefficients correspond to given-class anomalies. EFFECT: improved efficiency of detection. 2 dwg