Disclosed herein are various mechanisms for the adaptive cancellation of
radio frequency interference (RFI) in Discrete Multitone (DMT)-based
signal transmissions systems. various mechanisms for the adaptive
cancellation of radio frequency interference (RFI) in Discrete Multitone
(DMT) modulated signal transmissions systems. In at least one embodiment
of the present invention, RFI introduced by one or more RFI disturbers
(e.g., ham radios) into a DMT modulated signal may be detected by
calculating an RFI canceller coefficient for some or all of the DMT bins
of the signal, where the RFI canceller coefficient represents the
correlation between the noise at the corrupted bin and the reference RFI
noise. The RFI canceller coefficients for the corrupted bins may be
calculated using an LMS adaptation process. Those bins where the
magnitude of the corresponding RFI canceller coefficient is greater than
a certain threshold may be marked as corrupted by RFI. Further, one or
more bins having RFI canceller coefficients with the largest magnitudes
may be marked as reference disturber bins. The noise (e.g., error)
present in the identified reference disturber bins may be determined
using, for example, the slicer error. The RFI disturbance at some or all
of the corrupted bins then may be estimated based at least in part on the
error of the reference disturber bin proximal to the corrupted bin and
the RFI canceller coefficient for the corrupted bin. The received signal
then may be adjusted based on the RFI estimations for some or all of the
corrupted bins to reduce or eliminate the RFI disturbance in the signal.