Patent ID: 6057876
Filing Date: 2000-05-02
Classification: H03J,H04N

Abstract:
A CATV settop terminal which includes a receiver for receiving a plurality of CATV channel signals, the settop terminal comprising:a CATV channel selector for selecting a CATV channel signal from said plurality of CATV channel signals;a first frequency agile local oscillator for generating a first frequency for mixing with said selected CATV channel signal to generate a fixed high intermediate frequency signal;a filter for filtering said fixed high intermediate frequency signal;a second frequency agile local oscillator for generating a second frequency, at a predetermined value, for mixing with said filtered fixed high intermediate frequency signal to generate a fixed low intermediate frequency signal;a controller, responsive to said CATV channel selector, said controller including:means for determining said first frequency based on said selected CATV channel signal;means for comparing said first frequency with said second frequency to determine interfering oscillator difference beat (ODB) frequencies and for calculating a delta value based upon said ODB frequencies; andmeans for adjusting both said first and second frequencies by said delta value.