The present invention relates to electromagnetic tracking of medical devices. In order to provide improved tracking of medical devices, a wireless readout unit (10) for an electromagnetic tracking system of medical devices is provided. The wireless readout unit comprises a data input (12), a data processor (14) and a data output (16). The data input is configured to receive raw signals (18) from an electromagnetic sensor, and the data processor is configured to at least partly pre-process the raw signals provided by the data input for further transformation. Further, the data output is configured for data transmission of the at least partly pre-processed data to a control unit of an electromagnetic tracking system of medical devices. The data output provides a wireless data link (20) to a control unit.
