A method for operation of a distance sensor emits a transmission signal as transmission radiation, reflected by an object, the distance of which is to be measured, as reflection radiation, and received as a reflection signal. The reflection signal and a reference signal that occur at a receiver input are regulated to a predetermined ratio. The distance is determined during the regulation process. An auxiliary transmission antenna emits an auxiliary transmission signal as auxiliary measurement radiation, directly toward a reception antenna. Microwaves are used as the transmission and auxiliary transmission signals. The reception antenna receives the reflection radiation reflected by the object and passes it on to the receiver input as a reflection signal. The reception antenna receives the auxiliary measurement radiation directly and passes it on to the receiver input as an auxiliary reception signal which is evaluated as a reference signal when measurement radiation emission is suppressed.