Sampling arrangement for a television ghost signal cancellation system
Ghost canceling apparatus Patent #: 4502077
ApplicationNo. 06/657525 filed on 10/04/1984
US Classes:348/607, Noise or undesired signal reduction348/608, Processing at encoder or transmitter (e.g., pre-correction)455/295Modulation distortion or cross talk correction or elimination
ExaminersPrimary: Chin, Tommy P.
Attorney, Agent or Firm
International ClassesH03H 21/00 (20060101)
H04N 5/21 (20060101)
AbstractA multiple frequency adaptive filter system for filtering undesired periodic and/or correlated interference signals contained in the same frequency band as a desired input signal. The filter system is capable of filtering at least two sinusoidal interference signals and incorporates a negative feedback loop having a transfer function of that of narrow band-pass multiple filter. The feedback loop using interference frequencies generates a corresponding interference enhanced output signal. This enhanced output signal is combined with the input signal whereby to produce an error signal which corresponds to the desired signal contained in the input frequency band. A double or quadruple filter system is also described as examples of the present invention. The filter system is suitable for removing modulated sinusoidal interference and particularly for reducing TV co-channel interference.