The paper investigates the behavior of Hall-effect sensors (HES) operating in microwave frequency range. In order to evaluate the capabilities of small radars based on HES’s, the calculation of HES output voltage dependence on microwave intensity is carried out. It is shown that at power flow density I(t) = 10 μW/cm2 (a permissible value for a long-term human body exposure) the single GaAs sensor output Hall voltage U H ~ 0.03 μV.It is also demonstrated that integration of signals with due regard for their delays (as in the case of range-difference radar systems) gives an opportunity to obtain electromagnetic image of any point within the antenna coverage area with centimeter-level accuracy. The paper describes the experimental assembly and estimates the distances to the detected contrasting objects.