| 摘要 |
<p>A ghost cancellation system for filtering out ghosts in a received video signal including an active filter (14) having a filtering function defined by a first set of coefficients (akold) and having an input and an output. A transmitted ghost cancellation reference (GCR) signal is applied to the input of the active filter during a vertical blanking period to generate a filtered GCR signal at the output of active filter. The filtered GCR signal is compared with a ghostless GCR signal to obtain an error signal, and the filter coefficients are adjusted based on the error signal to obtain a set of new coefficients (aknew). The active filter includes a feedforword FIR filter (14-1) and an adder (14-3) serially connected between the input and the output, a feedback IIR filter (14-2) and a switch (14-4) serially connected between the output and the adder, the feedforward FIR filter and the feedback IIR filter having filtering functions defined by the coefficients.</p> |
