Improving the Accuracy of Bistatic Measurements Using a Reference Target

In this paper, a signal processing method using a reference target is developed. This method is based on comparing in the time domain the signal reflected from the sample under study and the signal reflected from a reference target. The use of this technique allows to increase the accuracy of measurements of bistatic scattering characteristics of small objects. The presence of a reference point reduces the angular positioning error of the antennas. Also, calibration to a reference target significantly reduces the effects of direct signal path between the transmit and receive antennas. The efficiency of this method compared to background subtraction in the time domain at bistatic angles greater than 120 degrees is shown. Amplitude of E-field of a flat metal sample was measured using this technique. It was shown that in the region of large bistatic angles, this method can significantly reduce the measurement error caused by the interaction of antennas.