Abstract: Objects of interest are detected which are below the horizon and which emit or are the cause of pressure wave fronts. By emitting radar pulses that interact with the pressure wave fronts that appear above the radar horizon and then by analysis of the detected echo signals in the range bins, the existence of a pressure wave front can be determined. Then, it is evaluated if this pressure wave front indicates the presence of an object of interest or not. The transmitted radar pulses in relation to the detected echoes can be used for identifying the object of interest. The emitted radar pulses may have a wavelength which is a multiple of the expected wavelength of the pressure wave fronts.