Testing device for testing a distance sensor operating with electromagnetic waves

A testing device for testing a distance sensor includes a receiving element for receiving an electromagnetic free-space wave as a receive signal, and a radiating element for radiating a simulated reflection signal. The receive signal or a signal derived therefrom is routed via a time delay circuit, and is thus time-delayed to a time-delayed signal. The time-delayed signal or a signal derived therefrom is radiated as the simulated reflection signal. The time delay circuit has an analog delay path and a digital delay path. The analog delay path implements shorter time delays than the digital delay path, apart from a possible overlap region. An input switch is used to switch the receive signal or the signal derived therefrom to the input of the analog delay path or to the input of the digital delay path, and the signal becomes the time-delayed signal after passing through the connected delay path.