The Ghost interference images are one of largest of poor picture quality not only in Television Broadcating system but also in CATV system. Especially ghost problem is getting more and more severe with the increasing of high-rise building. Ghost are time delayed, attenuated, and distorted version of the intended television signal. In general, both positive and negative signs can be assigned to the delay and attenuation variables. So, there are two parameters for ghost evaluation i.e. the attenuation R and the delay τ They are variable and the method of cancellation should be capable of following these variations. Advanced digital signal processing and filtering techniques make it feasible. In recent years, the research on ghost cancelling is focused on the utilization of the adaptive digital filters. The technique of adaptation in digital filter has proven to be a powerful and versatile means of signal processing in applications. The digital ghost cancellation filter for TV has made considerable progress and development. A digital ghost cancellor consists of signal processor, ghost cancelling filter network, error detection and correction circuits. The ghost cancelling filter network is an adaptive digital filter. It includes signal routing circuit and a digital transversal filter. In general, the digital transversal filter has two different modes, illustrated in Fig. 1. FF1 mode realizes a non-recursive configuration and FF2 mode realizes a recursive configuration.
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