Fmcw vco closed loop linearizer

Abstract

The present invention overcomes the problems discussed above by providing a linearizer apparatus for providing a linear ramp modulation for a voltage control oscillator (VCO), including voltage controlled oscillator means (VCO) having input and output terminals, and means for producing the output signal at its output terminal at the output frequency such that the output frequency corresponds to the voltage of a modulated tuning signal applied to the input terminal. A signal division means is coupled to the output of the VCO for producing a divided signal. A glass bulk acoustic delay means is coupled to the signal division means for producing a delayed signal. A first comparison signal generator means is coupled to the divided signal and the delayed signal for producing an IF signal which is proportional to the VCO output signal non-linearities. A reference oscillator means is provided for producing a reference signal. A second comparison signal generator means is coupled to the reference signal and the IF signal for producing an error signal. Finally, a summing means is coupled to a modulation waveform generator means and the error signal for producing a modulated tuning signal which is input to the VCO to frequency modulate the VCO.