Abstract: A reconfigurable system for the analogue processing of radio frequency signals in a satellite communications system, comprises means for receiving a signal within a pre-selected first intermediate frequency and agile filter means comprising a variable mixer stage and at least one variable filter, adapted to select one or more first frequency channels from the input signal, to amplify and provide automatic gain control of the selected first channel signals and to translate the selected first channels to one or more second frequency channel signals within a pre-selected second intermediate frequency band, wherein the agile filter means is controllable to allow in-orbit reconfiguration of the system. The first and second intermediate frequencies are selected so as to minimize conversion of the uplink and downlink signals.