Method and apparatus for cancelling radio frequency interference

A method and an apparatus for cancelling radio frequency interference in the analogue domain, in twisted pair connections when used for digital subscriber lines (DSL). When a disturbance signal couples onto the wire pair line as a common mode disturbance (c), the common mode disturbance is partially converted into a differential mode disturbance (r), and said differential mode disturbance interferes additively with said communication signal, resulting in a differential mode signal (d). The apparatus comprises means for sensing the common mode disturbance, means for converting the common mode disturbance into a reference signal (u), a modulator for applying a weight parameter (w) to the reference signal, and means for subtracting a differential mode cancellation signal, comprising the weighted reference signal, from the differential mode signal in order to obtain a minimised residual signal ( xi ). Preferably the apparatus comprises a demodulator devised to sense the residual signal and create an adaptation vector (q) for adapting the weight parameter in order to minimise said residual signal.