A method for amplifying an echo signal, in which an analog echo signal suitable for detection of a vehicle's surroundings is amplified by a gain dependent on the transit time of the echo signal, the analog echo signal being amplified by an amplifier having a plurality of outputs, each having a different gain, and a downstream A/D converter having a time-variable reference voltage. In the process, there is a switch between the different outputs of the amplifier at predefined switching points in time, and the reference voltage of the A/D converter varies over time between the switching points in time in such a way that the echo signal is present at the output of the A/D converter with a transit time-dependent total gain having a predefined characteristic.