Patent ID: 6163684
Filing Date: 2000-12-19
Classification: H03D,H03L,H04B

Abstract:
A tuner for receiving RF signals, said tuner comprising:an input filter receiving an RF signal having a plurality of channels and removing frequencies in said RF signal above an input cutoff frequency;a first mixer having a first input coupled to said input filter and a second input coupled to a first reference signal, wherein said first mixer generates a first IF signal;a first IF filter coupled to said first mixer and filtering said first IF signal;a second mixer having a first input coupled to said first IF filter and a second input coupled to a second reference signal, wherein said second mixer generates a second IF signal;a coherent reference phase lock loop fed by said second IF signal for generating a third reference signal; anda frequency synthesizer comprising wide band phase locked loops (PLLs) for generating said first and second reference signals, said frequency synthesizer having a phase noise characteristic that allows said coherent reference phase lock loop to have a narrow loop bandwidth.