Patent ID: 6169584
Filing Date: 2001-01-02
Classification: H04N

Abstract:
An automated modulation circuit for processing a video signal, comprising: means for detecting a comparison portion of said video signal; said comparison portion having an associated amplitude; means for normalizing the comparison portion amplitude according to a reference level which is different from the associated amplitude; means for detecting a reference portion of said video signal having an amplitude at the reference level in said video signal; means for generating a first error signal corresponding to a difference between the normalized comparison portion amplitude and the reference portion amplitude; and adjustment means responsive to said first error signal for adjusting a depth of modulation of said video signal, said adjustment means comprising: a microprocessor controller for converting said first error signal to a first adjustment signal; and a first charge pump for receiving said adjustment signal and providing a corresponding modulation depth control signal; wherein said corresponding modulation depth control signal is coupled to bias the video signal prior to modulation of said video signal by an RF carrier.