The invention concerns a system for extraction and analysis of significant radioelectric signals. It includes an overall number N of tracks. Each track V i includes a receptor connected to a digital acquisition device of analog signals generating a digital signal SN i . Each track V i includes a bank of polyphased filters, one or more digital signals SE i being generated by the bank of polyphased filters of the digital SN i signal emitted by the digital acquisition device of analog signals. The extracted digital signals SE i each have a frequency bandwidth less than that of the signal SN i received by the digital acquisition device of the analog signals. The system includes at least one device for the distribution of extracted digital signals adapted to receive extracted digital signals SE i of the banks of polyphased filters to one or more processing and storage unit/s. The processing and storage units are adapted to the analysis, characterisation and storage of the digital signals received. In particular, the invention is applicable to radio-surveillance systems using radioelectric emissions, whether in realtime or delayed action.