An evaluation unit 10 for a sensor arrangement for railway monitoring is described, the evaluation unit 10 comprising a connection to a position sensor 11 and a connection to a tracking sensor 12. The position sensor 11 is capable of detecting rail vehicles 19 passing over the position of the position sensor 11 on a railway track 14 and provides a position output signal 15. The tracking sensor 12 comprises a fibre optic sensor 16, which is capable of detecting the position of noise along the railway track 14 and the tracking sensor 12 provides a tracking output signal 18. The evaluation unit 10 provides an output signal 13 that depends on the position output signal 15 and the tracking output signal 18. Further, a sensor arrangement for railway monitoring and a method for evaluation of railway monitoring signals are described.