Investigation of Low-range Radar with Stepped Frequency Modulation while Indoor Operation

Based on the mathematical model, the influence is investigated of interference (due to repeated reflections of ranging signals with stepped frequency modulation from surfaces of a floor, ceiling and walls) upon the indoor operation of low-range radar while observing targets with small periodical displacements. A structure of interferential traces of the target is revealed and requirements are stated for delay resolution and resolution of bandwidth of ranging signals when there is no interferential fading and shift in range of target traces. Data of full-scale laboratory experiments are given that were obtained at the breadboard model of the step-frequency-modulated radar while observing oscillations of physical pendulums and breathing man. The obtained results are discussed.