In recent years, the use of different wireless and/or remote sensing techniques for identifying and tracking various objects has increased significantly. The detection and identification of targets navigating a given area are essential in order to prevent accidents and to take counter measures against illegal activities. Usually, radar systems are employed for the detection of objects. An original method for discriminating between electronic targets, by receiving at least two nonlinear mixing products near a harmonic, is presented. Specifically, the upper bounded inter element spacing provides a correct angular sampling accordingly to the Nyquist theorem and the lower bounded number of elements of the array ensures the continuity of the observation during multiple scans. (Radio Frequency Interference)RFI is particularly disruptive to harmonic radar since the signaltonoise ratio of the second order nonlinearity as is the case with traditional linear radar hence signalto interferenceplus noise ratio (SINR) decreases. Improved transponder design, MIMO, spectrum sensing, compressive sensing, adaptive bandwidth are among the techniques current in play for an improved performance of Radars. Harmonic radar are inherently highly sensitive. The harmonic radar must therefore avoid interference that could saturate the RF components and drive the RF components into their nonlinear operating region causing selfinduced harmonics. It’s vital that a Radar system mitigates the effect of RF in order to improve its efficiency. In this work, Multitone harmonic radar is presented. The radar transmits multiple closelyspaced tones and receives nonlinear mixing products as well as harmonics. Harmonic and Multitone responses are recorded from commerciallyavailable RF devices. . By properly designing the array of passive devices, the system is able to correctly observe the signal reflected from the targeted electronic device over successive scans of the radar. Target detection is demonstrated experimentally for a novel pulsed twotone harmonic radar. Experimental results are extrapolated to estimates radar design parameters to achieve an arbitrary standoff range of the object.
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