Automatic sensitivity control for radar level gauges

A radar level gauge system for determining the filling level of a filling material in a tank is disclosed. The system comprises an antenna device for emitting measuring signals towards the surface of the filling material and a receiver device for receiving echo signals from the tank. Further, the system comprises processing circuitry for determining the filling level of the tank based on said echo signal, wherein said processing circuitry is adapted to amplify the received echo signals in dependence of the distance from which the echo signals originates, in such a way that an echo signal from a lower filling level is more amplified than an echo signal from a higher filling level. The processing circuitry is adjustable to optimize the amplification of the echo signal based on the height of the tank. A corresponding processing circuitry and method of operation is also disclosed.